Currently, the same modules.load file is used for normal boot,
recovery/fastbootd and charger modes during first-stage init. This
means that during normal boot, the modules that are needed for
recovery and charger modes are loaded during first-stage init, which
is not required.

Add support for specifying a list of modules that are required for
booting into recovery or charger mode. This introduces two new
attributes to the kernel_images() macro called: modules_recovery_list
and modules_charger_list. Each attribute points to a list of modules
that are needed to boot into each mode respectively. This list can
be generated dynamically by concatenating the list of vendor_boot or
vendor_kernel_boot modules required for first stage init, along with
the list of modules needed to boot into each mode.

Defining these attributes also produces a file named
modules.load.[recovery/charger] in the initramfs, which init uses
instead of modules.load when booting into recovery or charger mode
respectively to load the first-stage init and recovery and charger
modules. In case of normal boot, init will use the modules.load
file, which will only contain the modules needed for first
stage init, and the recovery and charger modules will be loaded
from the vendor_dlkm partition during second-stage init.

Bug: 266752750
Change-Id: I11503b11683ef64cf0933b8641959ea5acd63ab1
Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com>
(cherry picked from commit b9ba4b67)
[isaacmanjarres: Re-wrote some of the commit message/implemented it
as part of kleaf. Also added tests for the new attributes.]
(cherry picked from commit d08605f4)
[isaacmanjarres: Resolved trivial merge conflicts when backporting
from main.]