purism/librem13: Set system type to laptop

Change-Id: I3ae80f5727e83a1c9210f0d13fa7fc32c5c79085
Signed-off-by: Youness Alaoui <youness.alaoui@puri.sm>
Reviewed-on: https://review.coreboot.org/18412
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Tested-by: build bot (Jenkins)

src/mainboard/purism/librem13/Kconfig

@@ -2,6 +2,7 @@ if BOARD_PURISM_LIBREM13
 
 config BOARD_SPECIFIC_OPTIONS # dummy
 	def_bool y
+	select SYSTEM_TYPE_LAPTOP
 	select BOARD_ROMSIZE_KB_8192
 	select EC_PURISM_LIBREM
 	select HAVE_ACPI_RESUME