x86/CPU/AMD: Remove amd_get_topology_early()

... and fold its function body into its single call site.

No functional changes:

  # arch/x86/kernel/cpu/amd.o:

   text    data     bss     dec     hex filename
   5994     385       1    6380    18ec amd.o.before
   5994     385       1    6380    18ec amd.o.after

md5:
   99ec6daa095b502297884e949c520f90  amd.o.before.asm
   99ec6daa095b502297884e949c520f90  amd.o.after.asm

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200123165811.5288-1-bp@alien8.de