#63 src/omx_reference_resource_manager.{h,c}: fix build with gcc 10

[Fabrice Fontaine]

Move globalIndex, listOfcomponentRegistered, globalComponentList and
globalWaitingComponentList from header to source file to fix the build
with gcc 10 which default to -fno-common:
https://gcc.gnu.org/gcc-10/porting_to.html

Fixes:

• http://autobuild.buildroot.org/results/0c02f845eabfbc276ee5989520a3c77fc47289ab

[Fabrice Fontaine]

Find attached a new version with the static qualifier