Unbreak with pre-C++11 compilers, e.g. with gcc 4.2.1 which is still the
default compiler on some tier-2 architectures like powerpc and sparc64,
by using identical types from C's <stdint.h> rather than C++'s <cstdint>
header file. While here, convert to USES+=localbase.

PR: 225171
Reported by: jhibbits