Also update the x86 asm.h to support this; we need it for libm assembler
anyway.
Also clean up the _FBSDID hack in <sys/cdefs.h>.
Change-Id: Iababd977b8110ec022bf7c93f4d62ece47630e7c
The kernel has supported this syscall for quite some time now,
but bionic did not. Now that there is a need for it, let's
add it to bionic.
Change-Id: Ifcef3e46f1438d79435b600c4e6063857ab16903