[OpenACC] Fix branch-in/out to not refer to a 'region'

'region' is not a term of art in OpenACC, so switch it to refer to
'Compute Construct', which is accurate/reflects the standard.

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -12204,5 +12204,5 @@ def err_acc_construct_appertainment
     : Error<"OpenACC construct '%0' cannot be used here; it can only "
             "be used in a statement context">;
 def err_acc_branch_in_out
-    : Error<"invalid branch %select{out of|into}0 OpenACC region">;
+    : Error<"invalid branch %select{out of|into}0 OpenACC Compute Construct">;
 } // end of sema component.

clang/test/SemaOpenACC/no-branch-in-out.c

@@ -14,15 +14,15 @@ void BreakContinue() {
     if (i == 2)
       continue;
 
-    break;  // expected-error{{invalid branch out of OpenACC region}}
+    break;  // expected-error{{invalid branch out of OpenACC Compute Construct}}
   }
 
   int j;
   switch(j) {
     case 0:
 #pragma acc parallel
     {
-      break; // expected-error{{invalid branch out of OpenACC region}}
+      break; // expected-error{{invalid branch out of OpenACC Compute Construct}}
     }
     case 1:
 #pragma acc parallel
@@ -34,7 +34,7 @@ void BreakContinue() {
 #pragma acc parallel
   for(int i = 0; i < 5; ++i) {
     if (i > 1)
-      break; // expected-error{{invalid branch out of OpenACC region}}
+      break; // expected-error{{invalid branch out of OpenACC Compute Construct}}
   }
 
 #pragma acc parallel
@@ -54,7 +54,7 @@ void BreakContinue() {
   for (int i =0; i < 5; ++i) {
 #pragma acc parallel
     {
-      continue; // expected-error{{invalid branch out of OpenACC region}}
+      continue; // expected-error{{invalid branch out of OpenACC Compute Construct}}
     }
   }
 
@@ -73,22 +73,22 @@ void BreakContinue() {
   for (int i =0; i < 5; ++i) {
 #pragma acc parallel
     {
-      break; // expected-error{{invalid branch out of OpenACC region}}
+      break; // expected-error{{invalid branch out of OpenACC Compute Construct}}
     }
   }
 
 #pragma acc parallel
   while (j) {
     --j;
     if (j > 4)
-      break; // expected-error{{invalid branch out of OpenACC region}}
+      break; // expected-error{{invalid branch out of OpenACC Compute Construct}}
   }
 
 #pragma acc parallel
   do {
     --j;
     if (j > 4)
-      break; // expected-error{{invalid branch out of OpenACC region}}
+      break; // expected-error{{invalid branch out of OpenACC Compute Construct}}
   } while (j );
 
 }