1. KERNEL_CRASH_DUMP should depends on KERNEL_PROC_KCORE (kexec use it)
2. select crashkernel mem size by totalmem
mem <= 256M disable crashkernel by default
mem >= 4G use 256M for crashkernel
mem >= 8G use 512M for crashkernel
default use 128M
3. set BOOT_IMAGE in kdump.init
4. resolve a "Unhandled rela relocation: R_X86_64_PLT32" error
Tested on x86_64
Signed-off-by: Chen Minqiang <ptpt52@gmail.com>
