Revert ".gitignore: ignore more scripts/config output"

This reverts commit c39d01596a.

It turns out the extra files were from an old config and are not
re/created by the new config.  Apologies for the noise.

Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>

.gitignore

@@ -16,10 +16,6 @@
 /overlay
 /package/feeds
 /package/openwrt-packages
-scripts/config/mconf_check
-scripts/config/zconf.hash.c
-scripts/config/zconf.lex.c
-scripts/config/zconf.tab.c
 /*.patch
 key-build*
 *.orig