arm64: compat: add support for big-endian (BE8) AArch32 binaries

This patch adds support for BE8 AArch32 tasks to the compat layer.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit a795a38eb91cf72c4a05e72a9c84e317ee179a48)

Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>

Conflicts:
	arch/arm64/include/asm/elf.h
diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
index aa57b15..212b0b6 100644
--- a/arch/arm64/include/asm/elf.h
+++ b/arch/arm64/include/asm/elf.h
@@ -165,7 +165,12 @@
 
 #ifdef CONFIG_COMPAT
 #define EM_ARM				40
+
+#ifdef __AARCH64EB__
+#define COMPAT_ELF_PLATFORM		("v8b")
+#else
 #define COMPAT_ELF_PLATFORM		("v8l")
+#endif
 
 #define COMPAT_ELF_ET_DYN_BASE		(randomize_et_dyn(2 * TASK_SIZE_32 / 3))