build: Add option to generate bl1 ROTPK

When TFM_DUMMY_PROVISIONING is set to OFF, the options
TFM_GENERATE_BL1_2_CM_SIGNING_KEY and TFM_GENERATE_BL1_2_DM_SIGNING_KEY
can be used to generate the BL1 CM and DM signing keys, similar to
MCUBOOT_GENERATE_SIGNING_KEYPAIR.

Signed-off-by: Gergely Kovacs <Gergely.Kovacs2@arm.com>
Change-Id: I5a9e8208aedf4cc355c2a1ca78284cadf3110bf6
5 files changed