toolchain/toolchain-wrapper.c: correct CCACHE_BASEDIR comment

Commit 1e97b2787331 ("ccache: support changing the output directory") added
the CCACHE_BASEDIR logic, but added a comment (presumably from cut'n'paste)
about compilercheck instead, fix that.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>

toolchain/toolchain-wrapper.c

@@ -526,7 +526,7 @@ int main(int argc, char **argv)
 		}
 #endif
 #ifdef BR_CCACHE_BASEDIR
-		/* Allow compilercheck to be overridden through the environment */
+		/* Allow basedir to be overridden through the environment */
 		if (setenv("CCACHE_BASEDIR", BR_CCACHE_BASEDIR, 0)) {
 			perror(__FILE__ ": Failed to set CCACHE_BASEDIR");
 			return 3;