alpha: VGA_HOSE depends on VGA_CONSOLE

arch/alpha/kernel/console.c:locate_and_init_vga uses vga_con, causing
build failures if VGA_CONSOLE was not set and MARVEL, TITAN, DP264, or
GENERIC alpha system types were set.

Reported-by: Raúl Porcel <armin76@gentoo.org>
Signed-off-by: Matt Turner <mattst88@gmail.com>

arch/alpha/Kconfig

@@ -477,7 +477,7 @@ config ALPHA_BROKEN_IRQ_MASK
 
 config VGA_HOSE
 	bool
-	depends on ALPHA_GENERIC || ALPHA_TITAN || ALPHA_MARVEL || ALPHA_TSUNAMI
+	depends on VGA_CONSOLE && (ALPHA_GENERIC || ALPHA_TITAN || ALPHA_MARVEL || ALPHA_TSUNAMI)
 	default y
 	help
 	  Support VGA on an arbitrary hose; needed for several platforms