PCI: Drop bogus default from ARCH_SUPPORTS_MSI

Options without prompts and without dependencies don't usefully have a
default value - they're intended to be selected from other options
only.
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

drivers/pci/Kconfig

@@ -3,7 +3,6 @@
 #
 config ARCH_SUPPORTS_MSI
 	bool
-	default n
 
 config PCI_MSI
 	bool "Message Signaled Interrupts (MSI and MSI-X)"