Add missing file in gitignore and comments

based on Linux source tree's .gitignore files

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/include/.gitignore b/include/.gitignore
index d8fda80..ab7d4c7 100644
--- a/include/.gitignore
+++ b/include/.gitignore
@@ -1,3 +1,4 @@
+/autoconf.mk*
 /asm
 /asm-ppc/arch
 /bmp_logo.h