arm64: Use generic sys_execve() implementation

This patch converts the arm64 port to use the generic sys_execve()
implementation removing the arm64-specific (compat_)sys_execve_wrapper()
functions.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/include/asm/unistd.h

@@ -26,4 +26,5 @@
 #define __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
 #define __ARCH_WANT_COMPAT_SYS_SENDFILE
 #endif
+#define __ARCH_WANT_SYS_EXECVE
 #include <uapi/asm/unistd.h>