Combine microdroid_ramdisk & microdroid_vendor_ramdisk images & this
will be microdroid_initrd in kernel_boot method. Also use the
initrd_bootconfig tool to attach bootconfig to it.
Also, collect all required bootconfigs. ABL, when verifying VBMeta, also
adds VBmeta digests & related configs to kernel command line. Without
ABL, we use bootconfig to send precomputed vbmeta digest. (Some of them
are computed using avbtool)
Test: Inspect the different build artifacts.
Bug: 240235424
Change-Id: I371c91db033a42bac6f0801a99490d18fc5dcdc1
Shikha Panwar