Wrap linux specific mseal syscall

Wrap linux specific mseal syscall

mseal takes address, size and flags.  Flags are reserved for
future use. Modern CPUs support memory permissions such as RW and
NX bits.  The mseal syscall takes address and size parameters to
additionally protect memory mapping against modifications.

FTR: https://docs.kernel.org/userspace-api/mseal.html

Declare a sys_mseal wrapper in priv_syswrap-linux.h and hook it
for {amd64,arm,arm64,mips64,nanomips,ppc32,ppc64,riscv64,s390x,x86}-linux
using LINX_ with PRE handler in syswrap-linux.c

https://bugs.kde.org/show_bug.cgi?id=505228