Minor fix for gtk-osx-gstreamer.modules

[Myshkin LeVine <myshlev verizon net>]

Hi John,
	When I was planning to install gstreamer and gst-plugins-base I came  
upon this comment in gtk-osx-gstreamer.modules: "<!-- Note: liboil/ 
motovec/motovec.c on PPC: comment out the defines in lines 43 & 44,  
they cause linkage failures -->". I decided to investigate this and  
my friend Google led me to a fix for those linkage failures. See the  
comment starting at line #83 here:

http://bitbucket.org/adium/adium/src/e9a00c46cd32/Utilities/dep-build- 
scripts/vv_dependencies_make.sh

I added "-DHAVE_SYMBOL_UNDERSCORE" to my CFLAGS in module_makeargs  
for liboil and those linkage failures went away. I thought you would  
like to know so that you can update gtk-osx-gstreamer.modules.
			Take care,
				  Myshkin LeVine