image_types_gbmc_dynamic: Support multiple DTS Let add_partition_info_fitimage can support multiple DTS Tested: build success with multiple KERNEL_DEVICETREE Google-Bug-Id: 432169384 Fusion-Link: https://fusion2.corp.google.com/39ad2d2f-e552-3c71-9cc4-74411eca69d0 https://fusion2.corp.google.com/2d88c962-2d62-31b8-8f80-c0d73070e563 https://fusion2.corp.google.com/75b703a8-ff2d-37b2-80c4-9c98aedd20b8 https://fusion2.corp.google.com/213fa53b-1bd3-3e0d-8695-8a5b2bece1f3 Change-Id: I9938abf5eeb24865dbffaaca0a9982fc6a99258b Signed-off-by: Steven Cho <cho.steven@inventec.corp-partner.google.com>