eeepc-wmi: Build fix

-tip testing found:

eeepc-wmi.c:(.text+0x36673c): undefined reference to `sparse_keymap_report_event'
drivers/built-in.o: In function `eeepc_wmi_init':
eeepc-wmi.c:(.init.text+0x19cd0): undefined reference to `sparse_keymap_setup'
eeepc-wmi.c:(.init.text+0x19cf0): undefined reference to `sparse_keymap_free'
eeepc-wmi.c:(.init.text+0x19d0b): undefined reference to `sparse_keymap_free'
drivers/built-in.o: In function `eeepc_wmi_exit':
eeepc-wmi.c:(.exit.text+0x2e87): undefined reference to `sparse_keymap_free'

To fix this select INPUT_SPARSEKMAP, like the ASUS driver does.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

drivers/platform/x86/Kconfig

@@ -390,6 +390,7 @@ config EEEPC_WMI
 	depends on ACPI_WMI
 	depends on INPUT
 	depends on EXPERIMENTAL
+	select INPUT_SPARSEKMAP
 	---help---
 	  Say Y here if you want to support WMI-based hotkeys on Eee PC laptops.