Re fixed minor warning

Turns out switching from 'size_t' to 'int' created different warnings.
Using 'unsigned int' solves all warnings.

Change-Id: I2c6c96fe6ed881bb6ce63717d53c8c5864273157
Reviewed-on: https://swiftshader-review.googlesource.com/5702
Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>
diff --git a/src/OpenGL/libGLESv2/utilities.cpp b/src/OpenGL/libGLESv2/utilities.cpp
index 73a5a4e..70ff932 100644
--- a/src/OpenGL/libGLESv2/utilities.cpp
+++ b/src/OpenGL/libGLESv2/utilities.cpp
@@ -1180,7 +1180,7 @@
 		return false;
 	}
 
-	std::string ParseUniformName(const std::string &name, int *outSubscript)
+	std::string ParseUniformName(const std::string &name, unsigned int *outSubscript)
 	{
 		// Strip any trailing array operator and retrieve the subscript
 		size_t open = name.find_last_of('[');