build: add code coverage

Add code coverage to build

Change-Id: I198d8bc9e6b99556582c14fc4dfd4c835150b5e0
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/.gitignore b/.gitignore
index dbd5f0a..69009e6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -10,12 +10,19 @@
 /test-driver
 /ylwrap
 
+# Code Coverage
+*.gcda
+*.gcno
+*.trs
+*-coverage*
+
 # http://www.gnu.org/software/autoconf
 
 /autom4te.cache
 /autoscan.log
 /autoscan-*.log
 /aclocal.m4
+/aminclude_static.am
 /compile
 /config.guess
 /config.h.in