ahci: Fix 'Invaild' typo

This fixes a spelling error in a message which can be output to the
console.

Signed-off-by: Taylor Hutt <thutt@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/block/ahci.c b/drivers/block/ahci.c
index 10fae88..20c5336 100644
--- a/drivers/block/ahci.c
+++ b/drivers/block/ahci.c
@@ -478,7 +478,7 @@
 	debug("Enter %s: for port %d\n", __func__, port);
 
 	if (port > probe_ent->n_ports) {
-		printf("Invaild port number %d\n", port);
+		printf("Invalid port number %d\n", port);
 		return -1;
 	}