Several compilers offer "long long" without claiming to support C99.

Considering how frequent __s64/__u64 are used our userspace headers are
anyway unusable without __s64/__u64 available.

Always offer __s64/__u64 to non-gcc non-C99 compilers - if they provide
"long long" that makes the headers compiling and if they don't they are
anyway screwed.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>