fix typos in comments and doc

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/docs/style-guide.txt b/docs/style-guide.txt
index a58931a..fdf6cfe 100644
--- a/docs/style-guide.txt
+++ b/docs/style-guide.txt
@@ -422,7 +422,7 @@
 Testing String Equivalence
 ~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-There's a right way and a wrong way to test for sting equivalence with
+There's a right way and a wrong way to test for string equivalence with
 strcmp():
 
 	The wrong way:
diff --git a/scripts/kconfig/util.c b/scripts/kconfig/util.c
index 0461a5f..ef4c832 100644
--- a/scripts/kconfig/util.c
+++ b/scripts/kconfig/util.c
@@ -57,7 +57,7 @@
 }
 
 
-/* Allocate initial growable sting */
+/* Allocate initial growable string */
 struct gstr str_new(void)
 {
 	struct gstr gs;