lib/kasprintf.c: use kmalloc_track_caller() to get accurate traces for kvasprintf

Previously kvasprintf() allocation was being done through kmalloc(),
thus producing an inaccurate trace report.

This is a common problem: in order to get accurate callsite tracing, a
lib/utils function shouldn't allocate kmalloc but instead use
kmalloc_track_caller.

Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/kasprintf.c

@@ -21,7 +21,7 @@ char *kvasprintf(gfp_t gfp, const char *fmt, va_list ap)
 	len = vsnprintf(NULL, 0, fmt, aq);
 	va_end(aq);
 
-	p = kmalloc(len+1, gfp);
+	p = kmalloc_track_caller(len+1, gfp);
 	if (!p)
 		return NULL;