Avoid memset in filter_intra_predictor module

Removed memset which is not required in the
av1_filter_intra_predictor module functions.

BUG=aomedia:2878

Change-Id: I48fffed4c81c63f1aec8a2fcf7f41099b21966fc
(cherry picked from commit cfaec3d1991e0914842a451991542d220f813867)
diff --git a/av1/common/reconintra.c b/av1/common/reconintra.c
index efb3794..1307a03 100644
--- a/av1/common/reconintra.c
+++ b/av1/common/reconintra.c
@@ -854,10 +854,6 @@
 
   assert(bw <= 32 && bh <= 32);
 
-  // The initialization is just for silencing Jenkins static analysis warnings
-  for (r = 0; r < bh + 1; ++r)
-    memset(buffer[r], 0, (bw + 1) * sizeof(buffer[0][0]));
-
   for (r = 0; r < bh; ++r) buffer[r + 1][0] = left[r];
   memcpy(buffer[0], &above[-1], (bw + 1) * sizeof(uint8_t));
 
@@ -905,10 +901,6 @@
 
   assert(bw <= 32 && bh <= 32);
 
-  // The initialization is just for silencing Jenkins static analysis warnings
-  for (r = 0; r < bh + 1; ++r)
-    memset(buffer[r], 0, (bw + 1) * sizeof(buffer[0][0]));
-
   for (r = 0; r < bh; ++r) buffer[r + 1][0] = left[r];
   memcpy(buffer[0], &above[-1], (bw + 1) * sizeof(buffer[0][0]));
 
diff --git a/av1/common/x86/filterintra_sse4.c b/av1/common/x86/filterintra_sse4.c
index c11edc1..99f4d99 100644
--- a/av1/common/x86/filterintra_sse4.c
+++ b/av1/common/x86/filterintra_sse4.c
@@ -27,10 +27,6 @@
 
   assert(bw <= 32 && bh <= 32);
 
-  // The initialization is just for silencing Jenkins static analysis warnings
-  for (r = 0; r < bh + 1; ++r)
-    memset(buffer[r], 0, (bw + 1) * sizeof(buffer[0][0]));
-
   for (r = 0; r < bh; ++r) buffer[r + 1][0] = left[r];
   memcpy(buffer[0], &above[-1], (bw + 1) * sizeof(uint8_t));