Revert D139752 "cmake: Enable 64bit off_t on 32bit glibc systems"

This reverts commit ae3e228a.

Seems that it may form a wrong command line for 32-bit Halide builds

`-D_FILE_OFFSET_BITS="64 -D_DEBUG -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -DSTDC_CONSTANT_MACROS -DSTDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS"` according to