efi/serial: re-init serial after efi detatchment

* This prevents haiku from "messing" with the gUART until
EFI boot services are exiting.
* The previous design meant that our loader started fiddling
with the gUART while EFI BIOS services were still being
used. On the SiFive, this broke serial output.
* Now, we guard on serial_init if EFI is unavailable, and
only fallback to direct UART usage when EFI is no longer
available.
* tldr; we're more closely managing serial across architectures
* serial_init use EFI and init it
* kernel_serial_handoff, stop using EFI
* serial_init, oh no EFI. Use gUART and Init it
* one gap is likely if no serial is available in EFI, but I
haven't seen that yet.

Change-Id: I644b51e4912272110435d288a95517d43a76740d
Reviewed-on: https://review.haiku-os.org/c/haiku/+/6200
Reviewed-by: Fredrik Holmqvist <fredrik.holmqvist@gmail.com>

efi/serial: Refactor EFI bios serial services

* Convert x86 direct port I/O to our standard gUART.
* sSerial is plainly EFI Serial or EFI Stdout
* gUART is plainly hardware serial now

Change-Id: I5730fbc0ce3427851e4e2d1d0aa8c55f7765e444
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5982
Reviewed-by: Alex von Gluck IV <kallisti5@unixzen.com>
Reviewed-by: Adrien Destugues <pulkomandy@pulkomandy.tk>

boot/efi: factor out generic mmu functions

This change moves the common functions related to EFI memory map
to arch/generic for arm, arm64, x86.

riscv64 and x86_64 shall be handled separately as they use some
more architecture-specific logic:
* riscv64 needs special treatment for the M-mode resident code
located at 0x80000000 which is reported as available in the
EFI memory map provided by u-boot.
* x86_64 has a slightly different logic for building the
memory regions list so some additional rework and testing will be
needed before it can be unified with the generic mmu functions.

Change-Id: I430c84dfc693c5b6f04c170dec8ffb1db2c2ace1
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5694
Reviewed-by: waddlesplash <waddlesplash@gmail.com>
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>

boot/efi/x86: move bootGDTDescriptor to local variable

Global variable gBootGDTDescriptor is used only in function arch_start_kernel()
so we can convert it to a local variable.

Change-Id: I8b6ad2c0903364bdcdcc1039aea6c9c09253fe09
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5663
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: David Karoly <karolyd577@gmail.com>

boot/efi/x86: implement SMP detection and bootup

* move common SMP initialization code to x86/arch_smp.cpp

* factor out arch-specific SMP initialization to
arch_smp_32.cpp resp arch_smp_64.cpp

* implement smp_trampoline for x86 32-bit EFI loader

* rename SMP trampoline for x86_64 to long_smp_trampoline

* add new argument virtKernelArgs to arch_smp_boot_other_cpus
as the kernel args are not identity mapped on 32-bit architectures

Change-Id: I30d0bb1fa9bfb08f6784a2af34eb83d6b64afa57
Reviewed-on: https://review.haiku-os.org/c/haiku/+/4869
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: waddlesplash <waddlesplash@gmail.com>
Reviewed-by: Fredrik Holmqvist <fredrik.holmqvist@gmail.com>

boot/efi/x86: implement MMU initialization and jump to kernel

Change-Id: Ie42c69f3851acae3a8184aa97ab2dd01c9485f46
Reviewed-on: https://review.haiku-os.org/c/haiku/+/4850
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: Alex von Gluck IV <kallisti5@unixzen.com>

boot/efi: add stubs for x86

Change-Id: I8d3dfa7cc07679a8b024df24f7cddb3a5bcec02c
Reviewed-on: https://review.haiku-os.org/c/haiku/+/4747
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: Jérôme Duval <jerome.duval@gmail.com>