Rename run_command() to builtin_run_command()

The current run_command() is only one of the parsing options - the other
is hush. We should not call run_command() when the hush parser is being
used. So we rename this function to better explain its purpose.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/common/cmd_bootm.c b/common/cmd_bootm.c
index d5745b1..2e3e159 100644
--- a/common/cmd_bootm.c
+++ b/common/cmd_bootm.c
@@ -1046,7 +1046,7 @@
 	int rcode = 0;
 
 #ifndef CONFIG_SYS_HUSH_PARSER
-	if (run_command(getenv("bootcmd"), flag) < 0)
+	if (builtin_run_command(getenv("bootcmd"), flag) < 0)
 		rcode = 1;
 #else
 	if (parse_string_outer(getenv("bootcmd"),