scripts/spelling.txt: add "intialization" pattern and fix typo instances

Fix typos and add the following to the scripts/spelling.txt:

  intialization||initialization

The "inintialization" in drivers/acpi/spcr.c is a different pattern but
I fixed it as well in this commit.

Link: http://lkml.kernel.org/r/1481573103-11329-16-git-send-email-yamada.masahiro@socionext.com


Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>