Documentation/: it's -> its where appropriate

Fix obvious cases of "it's" being used when "its" was meant.

Signed-off-by: Francis Galiegue <fgaliegue@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/Documentation/intel_txt.txt b/Documentation/intel_txt.txt
index f40a1f0..1423bcc 100644
--- a/Documentation/intel_txt.txt
+++ b/Documentation/intel_txt.txt
@@ -126,7 +126,7 @@
 o  Tboot adjusts the e820 table provided by the bootloader to reserve
    its own location in memory as well as to reserve certain other
    TXT-related regions.
-o  As part of it's launch, tboot DMA protects all of RAM (using the
+o  As part of its launch, tboot DMA protects all of RAM (using the
    VT-d PMRs).  Thus, the kernel must be booted with 'intel_iommu=on'
    in order to remove this blanket protection and use VT-d's
    page-level protection.