bionic is built without _FILE_OFFSET_BITS=64, so internally regoff_t
was 32-bit on LP32, but code compiled with _FILE_OFFSET_BITS would
expect rm_so and rm_eo in struct regmatch_t to be 64-bit, leading to
confusion.
Bug: http://b/23566443
Change-Id: Iae92fa545104068e4f64ce1977f5ec616859638c
I've also switched some tests to be positive rather than negative,
because !defined is slightly harder to reason about and there are
only two cases: bionic and glibc.
Change-Id: I8d3ac40420ca5aead3e88c69cf293f267273c8ef