Removed extraneous GCC warning flags.

auto/cc/gcc

diff --git a/auto/cc/gcc b/auto/cc/gcc
index 1740a5f..c27d857 100644
--- a/auto/cc/gcc
+++ b/auto/cc/gcc
@@ -156,9 +156,6 @@
     3.* | 4.* )
         # we have a lot of the unused function arguments
         CFLAGS="$CFLAGS -Wno-unused-parameter"
-        CFLAGS="$CFLAGS -Wunused-function"
-        CFLAGS="$CFLAGS -Wunused-variable"
-        CFLAGS="$CFLAGS -Wunused-value"
         # 4.2.1 shows the warning in wrong places
         #CFLAGS="$CFLAGS -Wunreachable-code"
     ;;