Currently it is possible to get the following bad config:

WARNING: unmet direct dependencies detected for SND_SOC_WM5110
  Depends on [n]: SOUND [=y] && !UML && SND [=y] && SND_SOC [=y] && MFD_WM5110 [=n]

commit ea00d952 ("ASoC: Use imply for SND_SOC_ALL_CODECS")
commit d8dd3f92 ("ASoC: Fix SND_SOC_ALL_CODECS imply misc fallout")

After these two patches the machine drivers still selects the
SND_SOC_WM5110 symbol which doesn't take account of the dependency
added on the MFD_WM5110 symbol, fix this by also adding a dependency on
MFD_WM5110 itself.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20200220125654.7064-1-ckeepax@opensource.cirrus.comSigned-off-by: Mark Brown <broonie@kernel.org>