Fix a whole bunch of compilation warnings reported by gcc 4.4

indra/llcommon/llstring.cpp

indra/llcommon/llstringtable.h

indra/llmath/v3math.h

indra/llmessage/lliobuffer.cpp

indra/llrender/llrendertarget.cpp

indra/llui/llmenugl.cpp

indra/newview/lldrawpoolbump.cpp

indra/newview/llface.cpp

indra/newview/llhudeffectlookat.cpp

indra/newview/llspatialpartition.cpp

indra/newview/lltoolpie.cpp

indra/newview/llviewercamera.cpp

indra/newview/llviewerkeyboard.cpp

indra/newview/llviewerobject.cpp

indra/newview/llvoavatar.cpp

indra/newview/llvosky.cpp

indra/newview/llvovolume.cpp