Remove stray printfs.

SwiftShader shouldn't print anything to stdout in Release builds.

Also refactor UNIMPLEMENTED macro to be able to take a formatted string
with arguments.

Bug b/73656151

Change-Id: Ibadbfba3371324ba1bd608bd51bdac5e5923a20e
Reviewed-on: https://swiftshader-review.googlesource.com/21108
Reviewed-by: Merck Hung <merckhung@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
diff --git a/src/Common/Configurator.cpp b/src/Common/Configurator.cpp
index 445305c..ead1d28 100644
--- a/src/Common/Configurator.cpp
+++ b/src/Common/Configurator.cpp
@@ -66,7 +66,7 @@
 
 				if(!isprint(line[0]))
 				{
-					printf("Failing on char %d\n", line[0]);
+				//	printf("Failing on char %d\n", line[0]);
 					file.close();
 					return false;
 				}