trogdor/sc7180: Clarify USE_QC_BLOBS requirements

This patch adds some Kconfig hints to make it clearer that the
USE_QC_BLOBS option is required for SC7180 boards and guide the user in
the right direction through menuconfig. Also add those little arrows to
the Trogdor board options that are there on most other boards.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: I973cae8026a229408a1a1817c4808b0266387ea7
Reviewed-on: https://review.coreboot.org/c/coreboot/+/45214
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Philip Chen <philipchen@google.com>

src/mainboard/google/trogdor/Kconfig.name

@@ -1,21 +1,28 @@
 comment "Trogdor"
 
+if USE_QC_BLOBS
+
 config BOARD_GOOGLE_BUBS
-	bool "Bubs"
+	bool "->  Bubs"
 	select BOARD_GOOGLE_TROGDOR_COMMON
 
 config BOARD_GOOGLE_COACHZ
-	bool "Coachz"
+	bool "-> Coachz"
 	select BOARD_GOOGLE_TROGDOR_COMMON
 
 config BOARD_GOOGLE_LAZOR
-	bool "Lazor"
+	bool "->  Lazor"
 	select BOARD_GOOGLE_TROGDOR_COMMON
 
 config BOARD_GOOGLE_POMPOM
-	bool "Pompom"
+	bool "->  Pompom"
 	select BOARD_GOOGLE_TROGDOR_COMMON
 
 config BOARD_GOOGLE_TROGDOR
-	bool "Trogdor"
+	bool "->  Trogdor"
 	select BOARD_GOOGLE_TROGDOR_COMMON
+
+endif
+
+comment "(Trogdor requires 'Allow QC blobs repository')"
+	depends on !USE_QC_BLOBS

src/soc/qualcomm/sc7180/Kconfig

@@ -2,6 +2,7 @@
 config SOC_QUALCOMM_SC7180
 	bool
 	default n
+	depends on USE_QC_BLOBS
 	select ARCH_BOOTBLOCK_ARMV8_64
 	select ARCH_RAMSTAGE_ARMV8_64
 	select ARCH_ROMSTAGE_ARMV8_64