musl: Update to latest on master

Bring in following changes

* fix missing volatile qualifier on lock in __get_locale
* remove ineffective compiler assist from printf
* fix undefined behavior in ptrace
* unify the use of FUTEX_PRIVATE
* fix undefined behavior in free
* reapply va_arg hacks removal to wprintf
* remove useless declarations in string.h
* allow specifying argv[0] when invoking a program via ldso command
* fix regression in dlopen promotion from RTLD_LOCAL to RTLD_GLOBAL
* ldso: avoid spurious & possible erroneous work for libs with no deps
* powerpc64: add single-instruction math functions
* fix clang CFLAGS checks and silence unused argument warnings
* s390x: add single-instruction math functions
* fix arm run-time abi string functions
* fix regression in getspnam[_r] error code for insufficient buffer size
* fix omission of microblaze user.h definitions
* fix iconv conversions for iso88592-iso885916
* handle errors from localtime_r in ctime_r
* set errno when getpw*_r, getgr*_r, and getspnam_r fail
* handle localtime errors in ctime
* handle mremap failure in realloc of mmap-serviced allocations
* getdate: correctly specify error number
* catopen: set errno to EOPNOTSUPP
* fix glob failure to match plain "/" to root directory
* use hard-coded sh4a atomic opcodes to avoid linker errors on sh

(From OE-Core rev: 1e109651acd53b8bad5bc2ccdf152d747a91f1ac)

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-core/musl/musl_git.bb

@@ -3,7 +3,7 @@
 
 require musl.inc
 
-SRCREV = "179766aa2ef06df854bc1d9616bf6f00ce49b7f9"
+SRCREV = "a08910fc2cc739f631b75b2d09b8d72a0d64d285"
 
 PV = "1.1.16+git${SRCPV}"