tidy: Clean up control flow jumps followed by else statements. (filters)

If the last statement in an "if" block unconditional changes the
control flow, then there is no need to follow that statement with an
else block.  Omitting the "else" statement and the indentation of the
subsequent block makes the code easier to follow.

https://clang.llvm.org/extra/clang-tidy/checks/readability-else-after-return.html

mythtv/filters/ivtc/pullup.c

@@ -596,7 +596,7 @@ static int decide_frame_length(struct pullup_context *c)
 			&& (f0->affinity != 1 || f1->affinity != -1) )
 			return 1;
 		if (f1->affinity == 1) return 1;
-		else return 2;
+                return 2;
 	case 3:
 		if (f2->affinity == 1) return 2;
 		else return 3;
@@ -606,7 +606,7 @@ static int decide_frame_length(struct pullup_context *c)
 		else if (f1->affinity == -1) return 2; /* covers 6 */
 		else if (f2->affinity == -1) { /* covers 2 */
 			if (f0->affinity == 1) return 3;
-			else return 1;
+                        return 1;
 		}
 		else return 2; /* the remaining 6 */
 	}

mythtv/filters/vflip/filter_vflip.c

@@ -57,10 +57,9 @@ static int comp(const void *va, const void *vb)
     int *b = (int *) vb;
     if (*a == *b)
         return 0;
-    else if (*a < *b)
+    if (*a < *b)
         return -1;
-    else
-        return 1;
+    return 1;
 }
 
 static int vflip(VideoFilter *vf, VideoFrame *frame, int field)