Add more clang-tidy checks.

This adds all the generic checks. There are some more project specific
ones that could be selected but this is a good start and has already
found some lint errors.

Change-Id: I7bb9d9347f5270862c2ff586eb7c86feead9e4bb
diff --git a/src/dlog.c b/src/dlog.c
index 38ccc85..5382096 100644
--- a/src/dlog.c
+++ b/src/dlog.c
@@ -163,7 +163,7 @@
 /*
  * Prints the given format string to the debug log.
  */
-void dlog(const char *str, ...)
+void dlog(const char *fmt, ...)
 {
 	static struct spinlock sl = SPINLOCK_INIT;
 	const char *p;
@@ -172,11 +172,11 @@
 	int flags;
 	char buf[2];
 
-	va_start(args, str);
+	va_start(args, fmt);
 
 	sl_lock(&sl);
 
-	for (p = str; *p; p++) {
+	for (p = fmt; *p; p++) {
 		switch (*p) {
 		default:
 			arch_putchar(*p);