res_tonedetect: Fix typos referring to wrong variables.

Fixes two typos that cause fax detection to not work.
One refers to the wrong frame variable, and the other
refers to the subclass.integer instead of the frametype
as it should.

ASTERISK-30192 #close

Change-Id: I7b35fdb7bcf25a29a212eee37c20812c64ab3ef1

res/res_tonedetect.c

@@ -940,8 +940,8 @@ static int scan_exec(struct ast_channel *chan, const char *data)
 				} else if (fax) {
 					char result;
 					frame2 = ast_dsp_process(chan, dsp2, frame2);
-					result = frame->subclass.integer;
-					if (result == AST_FRAME_DTMF) {
+					result = frame2->subclass.integer;
+					if (frame2->frametype == AST_FRAME_DTMF) {
 						if (result == 'e') {
 							pbx_builtin_setvar_helper(chan, "TONESCANSTATUS", "FAX");
 							match = 1;