Bump third_party/pigweed/repo from `ce0e3e2` to `c12c17d` #115535

Job	Run time
Build on Darwin (clang, simulated)	1h 14m 58s
Build on Linux (fake, gcc_release, clang, simulated)	50m 30s
Build on Linux (gcc_debug)	52m 4s
Build on Linux (python_lib)	18m 56s
Build on Linux (coverage)	18m 51s
Build on Linux (python lighting-app)	6m 14s
	3h 41m 33s

Provide feedback