arm64: Fix typos in arm_registers, add define for nGnRE.

Change-Id: I43aa971f2ead3a171af3c707539cbe08ff60cae5
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5262
Reviewed-by: Fredrik Holmqvist <fredrik.holmqvist@gmail.com>
Reviewed-by: David Karoly <karolyd577@gmail.com>
Reviewed-by: waddlesplash <waddlesplash@gmail.com>
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>

arm64: Add more headers for code compilation

This makes ARM64 target compile more files. This patch is one of
series of patches to support new architecture, as fixes in many
places are required just to compile the code.

Signed-off-by: Jaroslaw Pelczar <jarek@jpelczar.com>
Change-Id: Ia060612733cd3a0fcb781fec449da164ed635b8e
Reviewed-on: https://review.haiku-os.org/c/haiku/+/1807
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>