spl: Ensure all SPL symbols in Kconfig have some SPL dependency

Tighten up symbol dependencies in a number of places.  Ensure that a SPL
specific option has at least a direct dependency on SPL.  In places
where it's clear that we depend on something more specific, use that
dependency instead.  This means in a very small number of places we can
drop redundant dependencies.

Reported-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index 2c20dc7..0af53a6 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -29,6 +29,7 @@
 
 config SPL_POWER_LEGACY
 	bool "Legacy power support in SPL"
+	depends on SPL && !SPL_DM_PMIC
 	default y if POWER_LEGACY
 	help
 	  Note: This is a legacy option. Use SPL_DM_PMIC instead.