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/Debug.cpp b/src/Common/Debug.cpp
index c3a1921..acf469e 100644
--- a/src/Common/Debug.cpp
+++ b/src/Common/Debug.cpp
@@ -17,6 +17,8 @@
 #include <stdio.h>
 #include <stdarg.h>
 
+namespace sw
+{
 void trace(const char *format, ...)
 {
 	if(false)
@@ -34,3 +36,4 @@
 		}
 	}
 }
+}