fix spelling in API docu, command reply, logging, descriptions

sections: ctrl, gb, gsm, vty

Change-Id: Iac211b5cd8504da36b699777b95a2448dd7c3e70
diff --git a/src/gsm/lapd_core.c b/src/gsm/lapd_core.c
index a602d78..e0bbcab 100644
--- a/src/gsm/lapd_core.c
+++ b/src/gsm/lapd_core.c
@@ -861,7 +861,7 @@
 				if (memcmp(dl->cont_res->data, msg->data,
 								length)) {
 					LOGP(DLLAPD, LOGL_INFO, "Another SABM "
-					     "with diffrent content - "
+					     "with different content - "
 					     "ignoring! (dl=%p)\n", dl);
 					msgb_free(msg);
 					return 0;