Now that omnia-eeprom is marked nonshared building the cortex-a9 mvebu
subtarget will fail with:
ERROR: unable to select packages:
omnia-eeprom (no such package):
required by: world[omnia-eeprom]
This is because omnia-eeprom depends on TARGET_mvebu_cortexa9_DEVICE_cznic_turris-omnia
which will not be satisfied in buildbots since CONFIG_TARGET_ALL_PROFILES
and CONFIG_TARGET_PER_DEVICE_ROOTFS are set in which case
CONFIG_TARGET_mvebu_cortexa9_DEVICE_cznic_turris-omnia is not set.
So, lets simply depend on the mvebu/cortex-a9 subtarget.
Fixes: 371e7bef40 ("omnia-eeprom: Mark it nonshared")
Link: https://github.com/openwrt/openwrt/pull/17007
Signed-off-by: Robert Marko <robimarko@gmail.com>