soc/amd/common/data_fabric: print decoded control register contents

soc/amd/common/data_fabric: print decoded control register contents

Since all SoCs define the df_mmio_control union for the bits used in the
code, data_fabric_print_mmio_conf can take advantage of that and also
print a decoded version of those bits.

Output on Mandolin before the patch:

=== Data Fabric MMIO configuration registers ===
idx  control             base            limit
  0       93         fc000000         febfffff
  1       93      10000000000     ffffffffffff
  2       93         d0000000         f7ffffff
  3     1093         fed00000         fedfffff
  4       90                0             ffff
  5       90                0             ffff
  6       90                0             ffff
  7       90                0             ffff

Output on Mandolin with the patch:

=== Data Fabric MMIO configuration registers ===
idx             base            limit  control R W NP F-ID
  0         fc000000         febfffff       93 x x       9
  1      10000000000     ffffffffffff       93 x x       9
  2         d0000000         f7ffffff       93 x x       9
  3         fed00000         fedfffff     1093 x x  x    9
  4                0             ffff       90           9
  5                0             ffff       90           9
  6                0             ffff       90           9
  7                0             ffff       90           9

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I06e1d3a3e9abd664f59f2bb852394e7f723f2b30
Reviewed-on: https://review.coreboot.org/c/coreboot/+/72880
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Fred Reitberger <reitbergerfred@gmail.com>