use BB_EXECVP_or_die where appropriate

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/init/bootchartd.c b/init/bootchartd.c
index 5a1b3e8..ac3f261 100644
--- a/init/bootchartd.c
+++ b/init/bootchartd.c
@@ -441,8 +441,7 @@
 		pid_t pid = xvfork();
 		if (pid == 0) { /* child */
 			argv += 2;
-			execvp(argv[0], argv);
-			bb_perror_msg_and_die("can't execute '%s'", argv[0]);
+			BB_EXECVP_or_die(argv);
 		}
 		/* parent */
 		waitpid(pid, NULL, 0);