* libc/sys/arm/setjmp.S, libc/sys/arm/access.c: Move
files from libc/sys/arm to libc/machine/arm.
* libc/machine/arm/Makefile.am, libc/machine/arm/Makefile.in: Add
library build support for files moved from libc/sys/arm.
* libc/sys/arm/Makefile.am, libc/sys/arm/Makefile.in: Remove
references to access and setjmp.
* configure.host: Add checks for newlib_may_supply_syscalls to
determine whether or not to use sys/arm directory and use
special compiler flags: ARM_RDI_MONITOR and ARM_RDP_MONITOR.