open*(2) compat fixes (s390, arm64)

The usual rules for open()/openat()/open_by_handle_at() are
 1) native 32bit - don't force O_LARGEFILE in flags
 2) native 64bit - force O_LARGEFILE in flags
 3) compat on 64bit host - as for native 32bit
 4) native 32bit ABI for 64bit system (mips/n32, x86/x32) - as for
    native 64bit

There are only two exceptions - s390 compat has open() forcing
O_LARGEFILE and arm64 compat has open_by_handle_at() doing the same
thing.  The same binaries on native host (s390/31 and arm resp.) will
*not* force O_LARGEFILE, so IMO both are emulation bugs.

Objections? The fix is obvious...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/arm64/include/asm/unistd32.h

@@ -392,7 +392,7 @@ __SYSCALL(367, sys_fanotify_init)
 __SYSCALL(368, compat_sys_fanotify_mark_wrapper)
 __SYSCALL(369, sys_prlimit64)
 __SYSCALL(370, sys_name_to_handle_at)
-__SYSCALL(371, sys_open_by_handle_at)
+__SYSCALL(371, compat_sys_open_by_handle_at)
 __SYSCALL(372, sys_clock_adjtime)
 __SYSCALL(373, sys_syncfs)
 

arch/s390/kernel/compat_wrapper.S

@@ -28,7 +28,7 @@ ENTRY(sys32_open_wrapper)
 	llgtr	%r2,%r2			# const char *
 	lgfr	%r3,%r3			# int
 	lgfr	%r4,%r4			# int
-	jg	sys_open		# branch to system call
+	jg	compat_sys_open		# branch to system call
 
 ENTRY(sys32_close_wrapper)
 	llgfr	%r2,%r2			# unsigned int