roms/opensbi: Remove ELF images

Now that all RISC-V machines can use OpenSBI BIN images, we remove
OpenSBI ELF images and also exclude these images from BIOS build.

Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>

pc-bios/meson.build

@@ -80,8 +80,6 @@ blobs = files(
   'hppa-firmware.img',
   'opensbi-riscv32-generic-fw_dynamic.bin',
   'opensbi-riscv64-generic-fw_dynamic.bin',
-  'opensbi-riscv32-generic-fw_dynamic.elf',
-  'opensbi-riscv64-generic-fw_dynamic.elf',
   'npcm7xx_bootrom.bin',
 )