Fixes uclibc build as uclibc does not include backtrace functionality

Signed-of-by: Spenser Gilliland <spenser@gillilanding.com>
Signed-of-by: Markos Chandras <markos.chandras@imgtec.com>

Index: webkit-1.11.5/Source/WTF/wtf/Assertions.cpp
===================================================================
--- webkit-1.11.5.orig/Source/WTF/wtf/Assertions.cpp
+++ webkit-1.11.5/Source/WTF/wtf/Assertions.cpp
@@ -61,8 +61,10 @@
 #if (OS(DARWIN) || (OS(LINUX) && !defined(__UCLIBC__))) && !OS(ANDROID)
 #include <cxxabi.h>
 #include <dlfcn.h>
+#if !defined(__UCLIBC__)
 #include <execinfo.h>
 #endif
+#endif
 
 #if OS(ANDROID)
 #include "android/log.h"