kernel: Remove CONFIG_COMPAT

This removes support for executing old 32 bit applications on 64 bit ARM
and MIPS kernels.
On OpenWrt we normally compile all the user space applications on our
own and do not support third party binary only modules especial not 32
bit applications on 64 bit CPUs.

This reduces the attack surface on such systems and should also save
some memory.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

target/linux/mediatek/mt7622/config-4.14

@@ -19,7 +19,6 @@ CONFIG_ARCH_MEDIATEK=y
 CONFIG_ARCH_MMAP_RND_BITS=18
 CONFIG_ARCH_MMAP_RND_BITS_MAX=24
 CONFIG_ARCH_MMAP_RND_BITS_MIN=18
-CONFIG_ARCH_MMAP_RND_COMPAT_BITS=11
 CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MIN=11
 # CONFIG_ARCH_OPTIONAL_KERNEL_RWX is not set
 # CONFIG_ARCH_OPTIONAL_KERNEL_RWX_DEFAULT is not set
@@ -58,7 +57,6 @@ CONFIG_ARM64_VA_BITS=39
 CONFIG_ARM64_VA_BITS_39=y
 # CONFIG_ARM64_VA_BITS_48 is not set
 CONFIG_ARM64_VHE=y
-# CONFIG_ARMV8_DEPRECATED is not set
 CONFIG_ARM_AMBA=y
 CONFIG_ARM_ARCH_TIMER=y
 CONFIG_ARM_ARCH_TIMER_EVTSTREAM=y
@@ -75,7 +73,6 @@ CONFIG_AUDIT_ARCH_COMPAT_GENERIC=y
 CONFIG_BLK_DEV_SD=y
 CONFIG_BLK_MQ_PCI=y
 CONFIG_BLK_SCSI_REQUEST=y
-CONFIG_BLOCK_COMPAT=y
 # CONFIG_BOUNCE is not set
 CONFIG_BSD_PROCESS_ACCT=y
 CONFIG_BSD_PROCESS_ACCT_V3=y
@@ -108,10 +105,6 @@ CONFIG_COMMON_CLK_MT7622_AUDSYS=y
 CONFIG_COMMON_CLK_MT7622_ETHSYS=y
 CONFIG_COMMON_CLK_MT7622_HIFSYS=y
 # CONFIG_COMMON_CLK_MT8173 is not set
-CONFIG_COMPAT=y
-CONFIG_COMPAT_BINFMT_ELF=y
-CONFIG_COMPAT_NETLINK_MESSAGES=y
-CONFIG_COMPAT_OLD_SIGACTION=y
 CONFIG_CONSOLE_LOGLEVEL_DEFAULT=15
 # CONFIG_CPUFREQ_DT is not set
 # CONFIG_CPU_BIG_ENDIAN is not set
@@ -213,7 +206,6 @@ CONFIG_HAVE_ARCH_HUGE_VMAP=y
 CONFIG_HAVE_ARCH_JUMP_LABEL=y
 CONFIG_HAVE_ARCH_KASAN=y
 CONFIG_HAVE_ARCH_KGDB=y
-CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS=y
 CONFIG_HAVE_ARCH_PFN_VALID=y
 CONFIG_HAVE_ARCH_SECCOMP_FILTER=y
 CONFIG_HAVE_ARCH_TRACEHOOK=y
@@ -252,7 +244,6 @@ CONFIG_HAVE_PERF_USER_STACK_DUMP=y
 CONFIG_HAVE_RCU_TABLE_FREE=y
 CONFIG_HAVE_REGS_AND_STACK_ACCESS_API=y
 CONFIG_HAVE_SYSCALL_TRACEPOINTS=y
-CONFIG_HAVE_UID16=y
 CONFIG_HAVE_VIRT_CPU_ACCOUNTING_GEN=y
 # CONFIG_HUGETLBFS is not set
 # CONFIG_HW_RANDOM_MTK is not set
@@ -331,7 +322,6 @@ CONFIG_OF_NET=y
 CONFIG_OF_PCI=y
 CONFIG_OF_PCI_IRQ=y
 CONFIG_OF_RESERVED_MEM=y
-CONFIG_OLD_SIGSUSPEND3=y
 CONFIG_PADATA=y
 CONFIG_PARTITION_PERCPU=y
 CONFIG_PCI=y
@@ -419,7 +409,6 @@ CONFIG_SWAP=y
 CONFIG_SWIOTLB=y
 CONFIG_SWPHY=y
 CONFIG_SYSCTL_EXCEPTION_TRACE=y
-CONFIG_SYSVIPC_COMPAT=y
 CONFIG_SYS_SUPPORTS_HUGETLBFS=y
 CONFIG_THERMAL=y
 CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE=y