procd: seccomp/jail: Fix build error on arm with glibc

procd: seccomp/jail: Fix build error on arm with glibc

From: Peter Lundkvist <peter.lundkvist@gmail.com>

This fixes the make_syscall_h.sh script to recognize both
__NR_Linux, used by mips, and __NR_SYSCALL_BASE and
__ARM_NR_BASE used by arm.

Run-tested on arm (ipq806x) and mips (ath79), both with glibc.
Compile-tested and checked resulting syscall_names.h file wuth
glibc: aarch64, powerpc, x86_64, i486
musl: arm, mips

Fixes: FS#4194, FS#4195
Signed-off-by: Peter Lundkvist <peter.lundkvist@gmail.com>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>