Auto-sync with upstream branch master
Upstream commit: 51ea67d54882318c4fa5394c386f4816ddc22408
- powerpc: get_rounding_mode: utilize faster method to get rounding mode
- riscv: Do not use __has_include__
- powerpc: fegetexcept: utilize function instead of duplicating code
- iconv: Use __twalk_r in __gconv_release_shlib
- Fix iconv buffer handling with IGNORE error handler (swbz#18830)