MALLOC_DEBUG: Change fence magic number to be completely different from the freed magic number.

Race conditions between freeing a nul terminated string and
ast_strdup()'ing it are more likely to be detected if the fence and freed
magic numbers are completely different.
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Merged revisions 398703 from http://svn.asterisk.org/svn/asterisk/branches/1.8
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Merged revisions 398721 from http://svn.asterisk.org/svn/asterisk/branches/11
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Merged revisions 398726 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@398732 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/astmm.c

@@ -71,7 +71,7 @@ enum func_type {
 #undef vasprintf
 #undef asprintf
 
-#define FENCE_MAGIC		0xdeadbeef	/*!< Allocated memory high/low fence overwrite check. */
+#define FENCE_MAGIC		0xfeedbabe	/*!< Allocated memory high/low fence overwrite check. */
 #define FREED_MAGIC		0xdeaddead	/*!< Freed memory wipe filler. */
 #define MALLOC_FILLER	0x55		/*!< Malloced memory filler.  Must not be zero. */