[RESEND PATCH v5 01/11] kexec_file: allow archs to handle special regions while locating memory hole

Some architectures may have special memory regions, within the given memory range, which can't be used for the buffer in a kexec segment. Implement weak arch_kexec_locate_mem_hole() definition which arch code may override, to take care of special regions, while trying to locate a memory hole.

[PATCH v5 01/11] kexec_file: allow archs to handle special regions while locating memory hole

Some architectures may have special memory regions, within the given memory range, which can't be used for the buffer in a kexec segment. Implement weak arch_kexec_locate_mem_hole() definition which arch code may override, to take care of special regions, while trying to locate a memory hole.