binutils: fix crash when disassembling memory
binutils: fix crash when disassembling memory

There are times when the disassembler doesn't have a fully formed elf
(like when using gdb).  Change the extension logic to not require that
so we don't crash with segfaults.

manuelafm/riscv-gnu-toolchain,manuelafm/riscv-gnu-toolchain,manuelafm/riscv-gnu-toolchain