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/arch/x86/Kconfig b/arch/x86/Kconfig
index 1ac43e9..7e86c6a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -945,6 +945,7 @@
 
 config SPL_ACPI_GPE
 	bool "Support ACPI general-purpose events in SPL"
+	depends on SPL
 	help
 	  Enable a driver for ACPI GPEs to allow peripherals to send interrupts
 	  via ACPI to the OS. In U-Boot this is only used when U-Boot itself