s390: remove compat_wrapper.c

s390: remove compat_wrapper.c

Now that all these wrappers are automatically generated, we can
remove the entire file, and instead point to the regualar syscalls
like all other architectures do.

The 31-bit pointer extension is now handled in the __s390_sys_*()
wrappers.

Link: https://lore.kernel.org/lkml/20190116131527.2071570-6-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>