kleaf: refactor split_kernel_module_deps to return KernelModuleDepInfo

This change moves the conversion of kernel module dependencies into
KernelModuleDepInfo provider instances from the rules (kernel_module and
makefiles) into the split_kernel_module_deps utility function.

This simplifies the rule implementations and ensures that
kernel_module_deps lists consistently contain KernelModuleDepInfo
provider instances throughout the build process.

Bug: 394411899
Test: tools/bazel test //common-modules/virtual-device/kleaf_test:kleaf_test
Change-Id: I37bcd3ad77bd99b996e6060baf1acd172a7f7874