Remove *.gcna / *.gcno files from added module sources.

Asterisk uses a Makefile macro to associate additional sources with a
module.  This macro is responsible for creating clean targets but
previously left behind *.gcna and *.gcno files.

ASTERISK-25683 #close
Reported by yaron nahum

Change-Id: Idc0823fe80a25c42cefae901fde875e9fc38d8ea