docs: move x86 documentation into Documentation/arch/

JIRA: https://issues.redhat.com/browse/RHEL-68940
Conflicts:
  1) The Documentation/x86/boot.rst file and hunks related to this
     file are dropped due to a partial backport of this commit in
     RHEL commit a146bb4 ("docs: move x86 documentation into
     Documentation/arch/"). In part
  2) The x86/resctrl.rst and x86/topology.rst files are also dropped as
     they have been moved earlier by other RHEL commits.
  3) Some files are renamed and some are missing.

commit ff61f07
Author: Jonathan Corbet <corbet@lwn.net>
Date:   Tue, 14 Mar 2023 17:06:44 -0600

    docs: move x86 documentation into Documentation/arch/

    Move the x86 documentation under Documentation/arch/ as a way of cleaning
    up the top-level directory and making the structure of our docs more
    closely match the structure of the source directories it describes.

    All in-kernel references to the old paths have been updated.

    Acked-by: Dave Hansen <dave.hansen@linux.intel.com>
    Cc: linux-arch@vger.kernel.org
    Cc: x86@kernel.org
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Link: https://lore.kernel.org/lkml/20230315211523.108836-1-corbet@lwn.net/
    Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Signed-off-by: Waiman Long <longman@redhat.com>

Author: Waiman-Long

Documentation/admin-guide/RAS/main.rst

@@ -3153,7 +3153,7 @@
 
 	mce		[X86-32] Machine Check Exception
 
-	mce=option	[X86-64] See Documentation/x86/x86_64/boot-options.rst
+	mce=option	[X86-64] See Documentation/arch/x86/x86_64/boot-options.rst
 
 	md=		[HW] RAID subsystems devices and level
 			See Documentation/admin-guide/md.rst.
@@ -4615,7 +4615,7 @@
 			See Documentation/admin-guide/blockdev/paride.rst.
 
 	pirq=		[SMP,APIC] Manual mp-table setup
-			See Documentation/x86/i386/IO-APIC.rst.
+			See Documentation/arch/x86/i386/IO-APIC.rst.
 
 	plip=		[PPT,NET] Parallel port network link
 			Format: { parport<nr> | timid | 0 }
@@ -5897,7 +5897,7 @@
 
 	serialnumber	[BUGS=X86-32]
 
-	sev=option[,option...] [X86-64] See Documentation/x86/x86_64/boot-options.rst
+	sev=option[,option...] [X86-64] See Documentation/arch/x86/x86_64/boot-options.rst
 
 	shapers=	[NET]
 			Maximal number of shapers.