Preload the FEX fault report only where x86 loaders look
droiddeck-fex put the x86 libfaultreport.so in LD_PRELOAD, which FEX's own
arm64 loader reads too - and FEXServer's, and every child FEX's - so each
x86 start printed "ERROR: ld.so: object '.../libfaultreport.so' from
LD_PRELOAD cannot be preloaded", and an i386 child added "wrong ELF class".
It is now listed in the x86 runtime's own /etc/ld.so.preload, which only
the loaders inside FEX read, as /usr/$LIB/droiddeck/libfaultreport.so.
faultreport.c builds for i386 too, so 32-bit programs get the report as
well instead of an error.
