ArmPlatformPkg/Bds: Correct copy of an unaligned Unicode string

ArmPlatformPkg/Bds: Correct copy of an unaligned Unicode string

When a Unicode string is not stored in a 2-byte aligned memory area,
the StrnCpy() or StrCpy() functions can not be used to copy the string.
The string is now copied using CopyMem().

In the same function, a copy with "AsciiStrnCpy()" has also be replaced
with a copy using "CopyMem()" as the size of the string to copy is in
normal cases known. Another copy using "AsciiStrnCpy()" has been corrected
in order not to run off the array the string is copied into and to ensure
that the copied string has a final zero.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
Reviewed-by: Olivier Martin <olivier.martin@arm.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16009 6f19259b-4bc3-4df7-8a09-765794883524