[Darwin] Fix some format-related build warnings.

This fixes two error messages to avoid punctuation and contracted
negations.

gcc/ChangeLog:

2019-10-06  Iain Sandoe  <iain@sandoe.co.uk>

	* config/darwin.c (darwin_override_options): Adjust objective-c
	ABI version error messages to avoid punctuation and contracted
	negations.

From-SVN: r276635

gcc/ChangeLog

+2019-10-06  Iain Sandoe  <iain@sandoe.co.uk>
+
+	* config/darwin.c (darwin_override_options): Adjust objective-c
+	ABI version error messages to avoid punctuation and contracted
+	negations.
+
 2019-10-05  Jan Hubicka  <hubicka@ucw.cz>
 
 	* ipa-inline.c: Fix type; compute size rather than self_size

gcc/config/darwin.c

@@ -3152,13 +3152,14 @@ darwin_override_options (void)
   if (global_options_set.x_flag_objc_abi && flag_next_runtime)
     {
       if (TARGET_64BIT && global_options.x_flag_objc_abi < 2)
-	error_at (UNKNOWN_LOCATION, "%<-fobjc-abi-version%> >= 2 must be"
-				    " used for %<-m64%> targets with"
-				    " %<-fnext-runtime%>");
+	error_at (UNKNOWN_LOCATION, "%<-fobjc-abi-version%> must be greater"
+				    " than or equal to 2 for %<-m64%> targets"
+				    " with %<-fnext-runtime%>");
       if (!TARGET_64BIT && global_options.x_flag_objc_abi >= 2)
-	error_at (UNKNOWN_LOCATION, "%<-fobjc-abi-version%> >= 2 is not"
+	error_at (UNKNOWN_LOCATION, "%<-fobjc-abi-version%> %d is not"
 				    " supported on %<-m32%> targets with"
-				    " %<-fnext-runtime%>");
+				    " %<-fnext-runtime%>",
+				    global_options.x_flag_objc_abi);
     }
 
   /* Don't emit DWARF3/4 unless specifically selected.  This is a