Auto-sync with upstream master
Upstream commit: 11c4f5010c58029e73e656d5df4f8f42c9b8e877
- crypt: Use NSPR header files in addition to NSS header files (#1489339)
- math: Fix yn(n,0) without SVID wrapper (swbz#22244)
- math: Fix log2(0) and log(10) in downward rounding (swbz#22243)
- math: Add C++ versions of iscanonical for ldbl-96, ldbl-128ibm (swbz#22235)
- powerpc: Optimize memrchr for power8
- Hide various internal functions (swbz#18822)