msm: kgsl: Fix a compiler warning.

Fix compiler warning for a variable not
initialized.

Change-Id: I0616306c02ac8bb1c101d615879d831a022aaaea
Signed-off-by: Pu Chen <puchen@codeaurora.org>
diff --git a/drivers/gpu/msm/adreno.c b/drivers/gpu/msm/adreno.c
index 2f503ae..ff0a38f 100644
--- a/drivers/gpu/msm/adreno.c
+++ b/drivers/gpu/msm/adreno.c
@@ -253,7 +253,7 @@
 	int sizedwords = 0;
 	struct adreno_device *adreno_dev = ADRENO_DEVICE(device);
 	struct kgsl_memdesc **reg_map_desc;
-	void *reg_map_array;
+	void *reg_map_array = NULL;
 	int num_iommu_units, i;
 
 	if (!adreno_dev->drawctxt_active)