arm64: compat: fix compat types affecting struct compat_elf_prpsinfo

The compat_elf_prpsinfo structure does not match the arch/arm struct
elf_pspsinfo definition. As result NT_PRPSINFO note in core file
created by arm64 kernel for aarch32 (compat) process has wrong size.
So gdb cannot display command that caused process crash.

Fix is to change size of __compat_uid_t, __compat_gid_t so it would
match size of similar fields in arch/arm case.

Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>