Log Message:
nspr: Update to 4.29

Changelog:
NSPR 4.29 contains the following changes:
- Remove macOS Code Fragment Manager support code
- Remove XP_MACOSX and OS_TARGET=MacOSX
- Refresh config.guess and config.sub
- Remove NSPR's patch to config.sub
- Add support for e2k target (64-bit Elbrus 2000)