spapr: support only ELF kernel images

Currently everybody uses ELF kernel images with "-kernel" option on
pseries machine but QEMU still tries to boot from an image even it
fails to recognize it is ELF. This produces undefined behaviour if
the user tries a kernel image compiled for another architecture.

This removes support of raw kernel images.
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NAlexander Graf <agraf@suse.de>

hw/ppc/spapr.c

@@ -1312,11 +1312,6 @@ static void ppc_spapr_init(QEMUMachineInitArgs *args)
                                    NULL, &lowaddr, NULL, 0, ELF_MACHINE, 0);
             kernel_le = kernel_size > 0;
         }
-        if (kernel_size < 0) {
-            kernel_size = load_image_targphys(kernel_filename,
-                                              KERNEL_LOAD_ADDR,
-                                              load_limit - KERNEL_LOAD_ADDR);
-        }
         if (kernel_size < 0) {
             fprintf(stderr, "qemu: could not load kernel '%s'\n",
                     kernel_filename);