[x265] fix: uninitialized variable

[Satoshi Nakagawa]

# HG changeset patch
# User Satoshi Nakagawa <nakagawa424 at oki.com>
# Date 1393416382 -32400
#      Wed Feb 26 21:06:22 2014 +0900
# Node ID 4f072f41633375f2eb51c01ce05341aeb8fd16fb
# Parent  46207f6f5c8c7a85290c26467345f143e73a0bd8
fix: uninitialized variable

diff -r 46207f6f5c8c -r 4f072f416333 source/encoder/slicetype.cpp
--- a/source/encoder/slicetype.cpp	Wed Feb 26 00:43:46 2014 -0600
+++ b/source/encoder/slicetype.cpp	Wed Feb 26 21:06:22 2014 +0900
@@ -225,6 +225,8 @@
     {
         slicetypeAnalyse(frames, false);
     }
+    else
+        frames[0] = lastNonB;
 
     int j;
     for (j = 0; ipic && j < cfg->param.bframes + 2; ipic = ipic->m_next)