add pkgconfig file generation
update sets for ncurses pkgconfig change.
Remove additional files generated during ld.so build on make clean.
We don't have to pass the syscall number using the swi instruction.

This is part of AAPCS.  Our kernel already supports this.

ok drahn@
Properly align the stacks for 8-byte alignment. (AAPCS)

ok drahn@
Fix whitespaces.

ok drahn@
Implement fenv for vfp in libm.

ok drahn@
Don't need softfloat on eabi.

ok drahn@
Properly add target and build ABI to clang Makefile.

ok drahn@
Take care of the new target triples in Makefile.cross.

On eabi, our standard target triple will stay arm-unknown-bitrig0.1.
Though, to tell our compilers to target the correct cpu and abi.
For this, we will have to target armv7-unknown-bitrig0.1-gnueabihf.

Diff from drahn@
ok drahn@
Add missing mdoc_handler for .ll macro.

ok pedro@
Add text production macro for Bitrig (.Br).

ok pedro@
Our size_t's are unsigned long, so make ARM use that on AAPCS, too.

ok drahn@
Add patch for size_t commit in llvm.
For now, use SJLJ Exceptions on ARM.  This will prolly change soon.

ok drahn@
Add patch for llvm sjlj commit.
Compare MK_ARM_EABI in lower-case.

Diff from and ok drahn@
In kernelland the required aeabi functions can use the code we already have.

ok drahn@
Add MNT_SNAPSHOT flag.

Allow it to be passed to VFS_MOUNT and clear afterwards. Adapt mount(8).
Adapt mount_tmpfs(8) for upcoming snapshot support.

Add MNT_OPT; set ta_fspec. Copy in fspec to tmpfs_mount_t.