libgloss: pru: Remove sim ld script

libgloss: pru: Remove sim ld script

Binutils LD default linker script was recently fixed to allow memory
sizes to be set via command line. Use this feature to remove the special
sim linker script in libgloss.

It is acceptable to require newer Binutils version here because simulator
target is only used for regression testing the toolchain. Real HW
targets are not affected.

Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>