mb/google/sarien/Kconfig: Drop redundant 'select TPM2'

TPM2 set to yes by MAINBOARD_HAS_TPM2 at security/tpm/Kconfig file.

Change-Id: I815d545618e2e734f8e9b65731bbb4bed0b2d93d
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44933
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/mainboard/google/sarien/Kconfig

@@ -23,7 +23,6 @@ config BOARD_GOOGLE_BASEBOARD_SARIEN
 	select SPD_READ_BY_WORD
 	select SYSTEM_TYPE_LAPTOP if BOARD_GOOGLE_SARIEN
 	select SYSTEM_TYPE_CONVERTIBLE if BOARD_GOOGLE_ARCADA
-	select TPM2
 	select MAINBOARD_USES_IFD_EC_REGION
 	select MAINBOARD_USES_IFD_GBE_REGION if BOARD_GOOGLE_SARIEN
 	select USE_SAR