ath25: add kernel 5.10 support

Copy and refresh patches and config from 5.4 to 5.10. Most patches
require no more then automatic refresh. The only exception is the
Ethernet driver patch, which requires some more work:
* drop eth_change_mtu() usage since it was removed from the kernel,
  it anyway useless for drivers that utilizes alloc_etherdev();
* add the txqueue number argument to the .ndo_tx_timeout callback
  function;
* replace ioremap_nocache() which was finally removed from the kernel by
  the ioremap() with the same behaviour.

Switch target to the new kernel version.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
[use KERNEL_TESTING_PATCHVER for now]
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>

target/linux/ath25/config-5.10

@@ -0,0 +1,127 @@
+CONFIG_ADM6996_PHY=y
+CONFIG_AR2315_WDT=y
+CONFIG_AR8216_PHY=y
+CONFIG_ARCH_32BIT_OFF_T=y
+CONFIG_ARCH_HIBERNATION_POSSIBLE=y
+CONFIG_ARCH_MMAP_RND_BITS_MAX=15
+CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MAX=15
+CONFIG_ARCH_SUSPEND_POSSIBLE=y
+CONFIG_ATH25=y
+CONFIG_BLK_MQ_PCI=y
+CONFIG_CEVT_R4K=y
+CONFIG_CLONE_BACKWARDS=y
+CONFIG_CMDLINE="console=ttyS0,9600 rootfstype=squashfs,jffs2"
+CONFIG_CMDLINE_BOOL=y
+# CONFIG_CMDLINE_OVERRIDE is not set
+# CONFIG_COMMON_CLK is not set
+CONFIG_COMPAT_32BIT_TIME=y
+CONFIG_CPU_BIG_ENDIAN=y
+CONFIG_CPU_GENERIC_DUMP_TLB=y
+CONFIG_CPU_HAS_PREFETCH=y
+CONFIG_CPU_HAS_SYNC=y
+CONFIG_CPU_MIPS32=y
+CONFIG_CPU_MIPS32_R1=y
+CONFIG_CPU_MIPSR1=y
+CONFIG_CPU_NEEDS_NO_SMARTMIPS_OR_MICROMIPS=y
+CONFIG_CPU_R4K_CACHE_TLB=y
+CONFIG_CPU_SUPPORTS_32BIT_KERNEL=y
+CONFIG_CPU_SUPPORTS_HIGHMEM=y
+CONFIG_CRYPTO_LIB_POLY1305_RSIZE=2
+CONFIG_CRYPTO_RNG2=y
+CONFIG_CSRC_R4K=y
+CONFIG_DMA_NONCOHERENT=y
+CONFIG_EARLY_PRINTK=y
+CONFIG_ETHERNET_PACKET_MANGLE=y
+CONFIG_FORCE_PCI=y
+CONFIG_FW_LOADER_PAGED_BUF=y
+CONFIG_GENERIC_ATOMIC64=y
+CONFIG_GENERIC_CLOCKEVENTS=y
+CONFIG_GENERIC_CMOS_UPDATE=y
+CONFIG_GENERIC_CPU_AUTOPROBE=y
+CONFIG_GENERIC_GETTIMEOFDAY=y
+CONFIG_GENERIC_IOMAP=y
+CONFIG_GENERIC_IRQ_CHIP=y
+CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK=y
+CONFIG_GENERIC_IRQ_SHOW=y
+CONFIG_GENERIC_LIB_ASHLDI3=y
+CONFIG_GENERIC_LIB_ASHRDI3=y
+CONFIG_GENERIC_LIB_CMPDI2=y
+CONFIG_GENERIC_LIB_LSHRDI3=y
+CONFIG_GENERIC_LIB_UCMPDI2=y
+CONFIG_GENERIC_PCI_IOMAP=y
+CONFIG_GENERIC_SCHED_CLOCK=y
+CONFIG_GENERIC_SMP_IDLE_THREAD=y
+CONFIG_GENERIC_TIME_VSYSCALL=y
+CONFIG_GPIOLIB=y
+CONFIG_GPIO_AR2315=y
+CONFIG_GPIO_AR5312=y
+CONFIG_HANDLE_DOMAIN_IRQ=y
+CONFIG_HARDWARE_WATCHPOINTS=y
+CONFIG_HAS_DMA=y
+CONFIG_HAS_IOMEM=y
+CONFIG_HAS_IOPORT_MAP=y
+CONFIG_HW_RANDOM=y
+CONFIG_HZ_PERIODIC=y
+CONFIG_INITRAMFS_SOURCE=""
+CONFIG_IP17XX_PHY=y
+CONFIG_IRQ_DOMAIN=y
+CONFIG_IRQ_FORCED_THREADING=y
+CONFIG_IRQ_MIPS_CPU=y
+CONFIG_IRQ_WORK=y
+CONFIG_LEDS_GPIO=y
+CONFIG_LOCK_DEBUGGING_SUPPORT=y
+CONFIG_MDIO_BUS=y
+CONFIG_MDIO_DEVICE=y
+CONFIG_MDIO_DEVRES=y
+CONFIG_MEMFD_CREATE=y
+CONFIG_MIGRATION=y
+CONFIG_MIPS=y
+CONFIG_MIPS_ASID_BITS=8
+CONFIG_MIPS_ASID_SHIFT=0
+CONFIG_MIPS_CLOCK_VSYSCALL=y
+# CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND is not set
+CONFIG_MIPS_CMDLINE_FROM_BOOTLOADER=y
+CONFIG_MIPS_EBPF_JIT=y
+CONFIG_MIPS_L1_CACHE_SHIFT=5
+CONFIG_MIPS_LD_CAN_LINK_VDSO=y
+CONFIG_MODULES_USE_ELF_REL=y
+CONFIG_MTD_AR2315=y
+CONFIG_MTD_CFI_ADV_OPTIONS=y
+# CONFIG_MTD_CFI_GEOMETRY is not set
+# CONFIG_MTD_CFI_INTELEXT is not set
+CONFIG_MTD_MYLOADER_PARTS=y
+CONFIG_MTD_PHYSMAP=y
+CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK=-3
+CONFIG_MTD_REDBOOT_PARTS=y
+CONFIG_MVSWITCH_PHY=y
+CONFIG_NEED_DMA_MAP_STATE=y
+CONFIG_NEED_PER_CPU_KM=y
+CONFIG_NET_AR231X=y
+CONFIG_NO_GENERIC_PCI_IOPORT_MAP=y
+# CONFIG_OF is not set
+CONFIG_PCI=y
+CONFIG_PCI_AR2315=y
+CONFIG_PCI_DISABLE_COMMON_QUIRKS=y
+CONFIG_PCI_DOMAINS=y
+CONFIG_PCI_DRIVERS_LEGACY=y
+CONFIG_PERF_USE_VMALLOC=y
+CONFIG_PGTABLE_LEVELS=2
+CONFIG_PHYLIB=y
+CONFIG_SERIAL_8250_NR_UARTS=1
+CONFIG_SERIAL_8250_RUNTIME_UARTS=1
+CONFIG_SERIAL_MCTRL_GPIO=y
+CONFIG_SOC_AR2315=y
+CONFIG_SOC_AR5312=y
+CONFIG_SRCU=y
+# CONFIG_SWAP is not set
+CONFIG_SWCONFIG=y
+CONFIG_SYSCTL_EXCEPTION_TRACE=y
+CONFIG_SYS_HAS_CPU_MIPS32_R1=y
+CONFIG_SYS_HAS_EARLY_PRINTK=y
+CONFIG_SYS_SUPPORTS_32BIT_KERNEL=y
+CONFIG_SYS_SUPPORTS_ARBIT_HZ=y
+CONFIG_SYS_SUPPORTS_BIG_ENDIAN=y
+CONFIG_TARGET_ISA_REV=1
+CONFIG_TICK_CPU_ACCOUNTING=y
+CONFIG_TINY_SRCU=y
+CONFIG_USB_SUPPORT=y