[rend2-sp] Fix precaching related memory leaks

Gpu buffers, fbos, the gpu shaders and the image pool were allocated twice and leaking the second time... Looks like there's still something that leaks though.

shared/rd-rend2/tr_image.cpp

@@ -37,6 +37,7 @@ static struct ImagesPool
 	image_t *pPool;
 	ImagesPool *pNext;
 } *imagesPool;
+static bool imagePoolInitialized = false;
 
 static image_t *hashTable[FILE_HASH_SIZE];
 
@@ -3599,11 +3600,14 @@ Initialise the images pool allocator
 */
 void R_InitImagesPool()
 {
+	if (imagePoolInitialized)
+		return;
 	Com_Memset(hashTable, 0, sizeof(hashTable));
 
 	imagesPool = NULL;
 	tr.imagesFreeList = NULL;
 	R_ExtendImagesPool();
+	imagePoolInitialized = true;
 }
 
 /*
@@ -3644,6 +3648,7 @@ void R_DeleteTextures( void ) {
 		imagesPool = pNext;
 	}
 
+	imagePoolInitialized = false;
 	Com_Memset( glState.currenttextures, 0, sizeof( glState.currenttextures ) );
 	GL_SelectTexture( 1 );
 	qglBindTexture( GL_TEXTURE_2D, 0 );

shared/rd-rend2/tr_model.cpp

@@ -1598,9 +1598,6 @@ void R_SVModelInit()
 
 	R_InitImagesPool();
 	R_InitImages();
-	R_InitGPUBuffers();
-	FBO_Init();
-	GLSL_LoadGPUShaders();
 	R_InitShaders(qfalse);
 #endif