Quick fix for the type of the bitmap in sigset_t. It was an array of

Quick fix for the type of the bitmap in sigset_t.  It was an array of
4 u_ints but needs to be an array of 4 uint32_t's to work, at least
if unsigned ints have less than 32 bits.  It should be a non-array of
1 uint128_t on 128-bit machines, especially if u_int has 128 bits.
The headers that declare uint32_t (actually __uint32_t) are intentionally
not included here since this header should only be included by other
headers.

Fixed some style bugs (space instead of tab after #ifndef and #endif).