x86, arm64: Move ARCH_WANT_HUGE_PMD_SHARE config in arch/Kconfig

ARCH_WANT_HUGE_PMD_SHARE config was declared in both architectures:
move this declaration in arch/Kconfig and make those architectures
select it.
Signed-off-by: NAlexandre Ghiti <alex@ghiti.fr>
Reviewed-by: NPalmer Dabbelt <palmer@sifive.com>
Acked-by: NIngo Molnar <mingo@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> # for arm64
Reviewed-by: NHanjun Guo <guohanjun@huawei.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NPaul Walmsley <paul.walmsley@sifive.com>

arch/Kconfig

@@ -577,6 +577,9 @@ config HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
 config HAVE_ARCH_HUGE_VMAP
 	bool
 
+config ARCH_WANT_HUGE_PMD_SHARE
+	bool
+
 config HAVE_ARCH_SOFT_DIRTY
 	bool
 

arch/arm64/Kconfig

@@ -71,6 +71,7 @@ config ARM64
 	select ARCH_SUPPORTS_NUMA_BALANCING
 	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
 	select ARCH_WANT_FRAME_POINTERS
+	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
 	select ARCH_HAS_UBSAN_SANITIZE_ALL
 	select ARM_AMBA
 	select ARM_ARCH_TIMER
@@ -902,7 +903,6 @@ config SYS_SUPPORTS_HUGETLBFS
 	def_bool y
 
 config ARCH_WANT_HUGE_PMD_SHARE
-	def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
 
 config ARCH_HAS_CACHE_LINE_SIZE
 	def_bool y

arch/x86/Kconfig

@@ -93,6 +93,7 @@ config X86
 	select ARCH_USE_QUEUED_SPINLOCKS
 	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
 	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
+	select ARCH_WANT_HUGE_PMD_SHARE
 	select ARCH_WANTS_THP_SWAP		if X86_64
 	select BUILDTIME_EXTABLE_SORT
 	select CLKEVT_I8253
@@ -301,9 +302,6 @@ config ARCH_HIBERNATION_POSSIBLE
 config ARCH_SUSPEND_POSSIBLE
 	def_bool y
 
-config ARCH_WANT_HUGE_PMD_SHARE
-	def_bool y
-
 config ARCH_WANT_GENERAL_HUGETLB
 	def_bool y