kconfig: Replace some single-symbol 'if's with 'depends on'

I think people might be reading differences into 'if' and 'depends on'
that aren't there, like maybe 'if' being needed to "hide" a symbol,
while 'depends on' just adds a dependency.

There are no differences between 'if' and 'depends on'. 'if' is just a
shorthand for 'depends on'. They work the same when it comes to creating
implicit menus too.

The way symbols get "hidden" is through their dependencies not being
satisfied ('if'/'depends on' get copied up as a dependency on the
prompt).

Since 'if' and 'depends on' are the same, an 'if' with just a single
symbol in it can be replaced with a 'depends on'. IMO, it's best to
avoid 'if' there as a style choice too, because it confuses people into
thinking there's deep Kconfig magic going on that requires 'if'.

Going for 'depends on' can also remove some nested 'if's, which
generates nicer symbol information and docs, because nested 'if's really
are so simple/dumb that they just add the dependencies from both 'if's
to all symbols within.

Replace a bunch of single-symbol 'if's with 'depends on' to despam the
Kconfig files a bit and make it clearer how things work. Also do some
other minor related dependency refactoring.

The replacement isn't complete. Will fix up the rest later. Splitting it
a bit to make it more manageable.

(Everything above is true for choices, menus, and comments as well.)

Detected by tweaking the Kconfiglib parsing code. It's impossible to
detect after parsing, because 'if' turns into 'depends on'.

Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>

drivers/espi/Kconfig

@@ -40,19 +40,16 @@ config ESPI_VWIRE_CHANNEL
 	help
 	  eSPI Controller supports virtual wires channel.
 
-if ESPI_VWIRE_CHANNEL
-
 config ESPI_AUTOMATIC_WARNING_ACKNOWLEDGE
 	bool "Automatic acknowledge for eSPI HOST warnings"
 	default y
+	depends on ESPI_VWIRE_CHANNEL
 	help
 	  Enable automatic acknowledge from eSPI slave towards eSPI host
 	  whenever it receives suspend or reset warning.
 	  If this is disabled, it means the app wants to be give the opportunity
 	  to prepare for either HOST suspend or reset.
 
-endif # ESPI_VWIRE_CHANNEL
-
 config ESPI_OOB_CHANNEL
 	bool "eSPI Out-of-band channel"
 	help