Restore top-level .gitignore; testbuild.sh must distinguish CONFIG_ARM_TOOLCHAIN_GNU from other symbols that begin with the same string

.gitignore

@@ -1,15 +1,3 @@
-.depend
-Make.dep
-*.o
-*.a
-*.d
-*.i
-*~
-.swp
-.*.swp
-core
-.gdbinit
-cscope.out
 /.config
 /.config.old
 /.version

tools/testbuild.sh

@@ -180,7 +180,7 @@ function configure {
     fi
 
     if [ "X$toolchain" != "X" ]; then
-        setting=`grep TOOLCHAIN $nuttx/.config | grep -v CONFIG_ARM_TOOLCHAIN_GNU | grep =y`
+        setting=`grep TOOLCHAIN $nuttx/.config | grep -v CONFIG_ARM_TOOLCHAIN_GNU=y | grep =y`
         varname=`echo $setting | cut -d'=' -f1`
         if [ ! -z "varname" ]; then
             echo "  Disabling $varname"