readelf: fix printing of DT_FILTER and some other DT_* values

MFC r321045: readelf: fix printing of DT_FILTER and some other DT_* values

Some non-processor-specific DT_* values overlap the range DT_LOPROC to
DT_HIPROC. Handle common ones first, then the processor-specific ones.

MFC r321046: readelf: correct printing of DT_FILTER and DT_AUXILIARY values

Previously these were shown only for MIPS objects.

Obtained from: ELF Tool Chain r3563, r3564
Sponsored by: The FreeBSD Foundation