libdvr: LGE Coverity aml dvr report [1/1]

PD#TV-61227

Problem:
LGE report Coverity errors of libdvr.

Solution:
Fix 19 out of 42 errors reported by Coverity for the 2nd round
including BUFFER_SIZE, CHECKED_RETURN, LOCK, NO_EFFECT, PRINTF_ARGS,
RESOURCE_LEAK, STRING_NULL, UNINIT, UNUSED_VALUE and USE_AFTER_FREE

Verify:
Locally tested OK in AH212 RDK environment.

Signed-off-by: Wentao.MA <wentao.ma@amlogic.com>

Change-Id: I0e4e6aa96b73220ee79163c8427eaf9cb9c38d62
diff --git a/src/dvb_utils.c b/src/dvb_utils.c
index aecf126..6e638b8 100644
--- a/src/dvb_utils.c
+++ b/src/dvb_utils.c
@@ -71,7 +71,7 @@
     char node2[20] = {0};
     int fd = -1;
     int fd2 = -1;
-    int r;
+    int r = 0;
 
     snprintf(node, sizeof(node), "/sys/class/stb/demux%d_source", dmx_idx);
     snprintf(node2, sizeof(node2), "/dev/dvb0.demux%d", dmx_idx);
@@ -212,7 +212,8 @@
     int fd = -1;
     int fd2 = -1;
     char buf[32] = {0};
-    int r, source_no;
+    int r = 0;
+    int source_no = 0;
 
     snprintf(node, sizeof(node), "/sys/class/stb/demux%d_source", dmx_idx);
     snprintf(node2, sizeof(node2), "/dev/dvb0.demux%d", dmx_idx);