get_linux_version_code: don't fail on Linux version strints like "3.0…

…-foo"

Signed-off-by: Andreas Oberritter <obi@opendreambox.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

libbb/kernel_version.c

@@ -20,18 +20,15 @@
 int FAST_FUNC get_linux_version_code(void)
 {
 	struct utsname name;
-	char *s;
+	char *s, *t;
 	int i, r;
 
-	if (uname(&name) == -1) {
-		bb_perror_msg("can't get system information");
-		return 0;
-	}
-
+	uname(&name); /* never fails */
 	s = name.release;
 	r = 0;
 	for (i = 0; i < 3; i++) {
-		r = r * 256 + atoi(strtok(s, "."));
+		t = strtok(s, ".");
+		r = r * 256 + (t ? atoi(t) : 0);
 		s = NULL;
 	}
 	return r;