docs: arm64: fix trivial spelling enought to enough in memory.rst

Fix trivial spelling error enought to enough in memory.rst.

Cc: trivial@kernel.org
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Will Deacon <will@kernel.org>

Documentation/arm64/memory.rst

@@ -129,7 +129,7 @@ this logic.
 
 As a single binary will need to support both 48-bit and 52-bit VA
 spaces, the VMEMMAP must be sized large enough for 52-bit VAs and
-also must be sized large enought to accommodate a fixed PAGE_OFFSET.
+also must be sized large enough to accommodate a fixed PAGE_OFFSET.
 
 Most code in the kernel should not need to consider the VA_BITS, for
 code that does need to know the VA size the variables are