Add support to sparc for loading a real bios image.

diff -p -u -r1.52 sun4m.c
@@ -49,7 +49,7 @@
 #define KERNEL_LOAD_ADDR     0x00004000
 #define CMDLINE_ADDR         0x007ff000
 #define INITRD_LOAD_ADDR     0x00800000
-#define PROM_SIZE_MAX        (256 * 1024)
+#define PROM_SIZE_MAX        (512 * 1024)
 #define PROM_PADDR           0xff0000000ULL
 #define PROM_VADDR           0xffd00000
 #define PROM_FILENAME	     "openbios-sparc32"

@@ -435,9 +435,12 @@ static void sun4m_load_kernel(long vram_
     snprintf(buf, sizeof(buf), "%s/%s", bios_dir, bios_name);
     ret = load_elf(buf, PROM_PADDR - PROM_VADDR, NULL, NULL, NULL);
     if (ret < 0) {
-	fprintf(stderr, "qemu: could not load prom '%s'\n",
+        ret = load_image(buf, phys_ram_base + prom_offset);
+	if (ret < 0) {
+	    fprintf(stderr, "qemu: could not load prom '%s'\n",
 		buf);
-	exit(1);
+	    exit(1);
+	}
     }
 
     kernel_size = 0;