BaseTools/tools_def.template: Add -gdwarf to XCODE5 X64

BaseTools/tools_def.template: Add -gdwarf to XCODE5 X64

Add -gdwarf to XCODE5 X64 builds to generate symbols for
source level debug using lldb.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Signed-off-by: Andrew Fish <afish@apple.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
Acked-by: Jordan Justen <jordan.l.justen@intel.com>
Tested-by: Andrew Fish <afish@apple.com>