x86/microcode: Add explicit CPU vendor dependency

Add an explicit dependency to the respective CPU vendor so that the
respective microcode support for it gets built only when that support is
enabled.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/8ead0da9-9545-b10d-e3db-7df1a1f219e4@infradead.org

arch/x86/Kconfig

@@ -1313,7 +1313,7 @@ config MICROCODE
 
 config MICROCODE_INTEL
 	bool "Intel microcode loading support"
-	depends on MICROCODE
+	depends on CPU_SUP_INTEL && MICROCODE
 	default MICROCODE
 	help
 	  This options enables microcode patch loading support for Intel
@@ -1325,7 +1325,7 @@ config MICROCODE_INTEL
 
 config MICROCODE_AMD
 	bool "AMD microcode loading support"
-	depends on MICROCODE
+	depends on CPU_SUP_AMD && MICROCODE
 	help
 	  If you select this option, microcode patch loading support for AMD
 	  processors will be enabled.