Add syscall entries for new linux syscalls

Add syscall entries for new linux syscalls

* linux/i386/syscallent.h: Update process_vm_writev handler.
* linux/powerpc/syscallent.h: Likewise.
* linux/x86_64/syscallent.h: Likewise.
* linux/alpha/syscallent.h: Add entries for accept4 and sendmmsg.
* linux/arm/syscallent.h: Add entries for process_vm_readv and
process_vm_writev.
* linux/m68k/syscallent.h: Likewise.
* linux/mips/syscallent.h: Likewise.
* linux/s390/syscallent.h: Likewise.
* linux/s390x/syscallent.h: Likewise.
* linux/sh/syscallent.h: Likewise.
* linux/sh64/syscallent.h: Likewise.
* linux/sparc/syscallent.h: Likewise.
* linux/ia64/syscallent.h: Add entries for process_vm_readv,
process_vm_writev and accept4.
* linux/microblaze/syscallent.h: Add entries for sendmmsg,
process_vm_readv and process_vm_writev.