Fix warnings raised during release builds

Bug: b/123933266
Change-Id: If4dc4858c8a81dd5e7b3510a08e7dbae74051483
Reviewed-on: https://swiftshader-review.googlesource.com/c/25556
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Tested-by: Ben Clayton <bclayton@google.com>

src/OpenGL/libGLES_CM/Context.cpp

diff --git a/src/OpenGL/libGLES_CM/Context.cpp b/src/OpenGL/libGLES_CM/Context.cpp
index 811234e..45c26ee 100644
--- a/src/OpenGL/libGLES_CM/Context.cpp
+++ b/src/OpenGL/libGLES_CM/Context.cpp
@@ -2510,10 +2510,10 @@
 		{
 			for(int i = 0; i < rect.x1 - rect.x0; i++)
 			{
-				float r;
-				float g;
-				float b;
-				float a;
+				float r = 0.f;
+				float g = 0.f;
+				float b = 0.f;
+				float a = 0.f;
 
 				switch(renderTarget->getExternalFormat())
 				{

src/OpenGL/libGLES_CM/libGLES_CM.cpp

diff --git a/src/OpenGL/libGLES_CM/libGLES_CM.cpp b/src/OpenGL/libGLES_CM/libGLES_CM.cpp
index c7cf691..31a2c29 100644
--- a/src/OpenGL/libGLES_CM/libGLES_CM.cpp
+++ b/src/OpenGL/libGLES_CM/libGLES_CM.cpp
@@ -2104,7 +2104,7 @@
 			return error(GL_INVALID_ENUM);
 		}
 
-		GLenum attachmentObjectType;   // Type category
+		GLenum attachmentObjectType = GL_NONE;   // Type category
 		if(attachmentType == GL_NONE_OES || attachmentType == GL_RENDERBUFFER_OES)
 		{
 			attachmentObjectType = attachmentType;