libprotobuf-c-nano-enable_malloc: mk -> bp

Note, removes "LOCAL_C_EXTENSION := .c" lines. LOCAL_C_EXTENSION is not
in Android make and only appears in this one file.

Test: (sanity) boot internal marlin
Test: links
Bug: 37429672
Change-Id: Ifcfa28c257cc5b986086a1d6108687da8b04a027
2 files changed