mb/google/eve: select SYSTEM_TYPE_CONVERTIBLE

select SYSTEM_TYPE_CONVERTIBLE, which properly sets the
SMBIOS chassis type, and allows the OS driver to
recognize tablet mode capability

Change-Id: Ic61659e9fa6f7428afd1f018fb8cb25fe49e8747
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37903
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/mainboard/google/eve/Kconfig

@@ -21,6 +21,7 @@ config BOARD_SPECIFIC_OPTIONS
 	select MAINBOARD_HAS_LIBGFXINIT
 	select MAINBOARD_HAS_TPM2
 	select SOC_INTEL_KABYLAKE
+	select SYSTEM_TYPE_CONVERTIBLE
 
 config VBOOT
 	select EC_GOOGLE_CHROMEEC_SWITCHES