package/musl: bump to version 1.1.23

This version merges the RISC-V (64-bit) port and new math library
implementations of log, exp, and pow. Internals of how (non-cancellable)
syscalls are performed have been overhauled so that all code necessary to make
the syscall resides in the arch-provided header and is inlinable. In the
process, bugs in the implementation of mips and microblaze syscall mechanisms
were found and fixed. Several other bugs were fixed as well, including a
potentially serious one in the layout of static TLS for shared libraries on
archs that use "TLS variant I" layout.

A couple behaviors that were clearly undesirable but arguably mandated by POSIX
have been fixed as a result of POSIX intepretations rendering them unnecessary.

Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks>
Tested-by: Mark Corbin <mark.corbin@embecosm.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>