arch-arm: Semihosting, fix SYS_FLEN

SYS_FLEN was incorrectly handled as SYS_ISTTY. This patch fixes this
behaviour.

Change-Id: I66e0b97d8b44d2cb78e0b1bb940fd6f4b52c658f
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23752
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
1 file changed