docs: Reapply some of Marek's typo fixes.
There were some typos too.
diff --git a/docs/patents.txt b/docs/patents.txt
index 6af830e..3834e25 100644
--- a/docs/patents.txt
+++ b/docs/patents.txt
@@ -12,8 +12,8 @@
The source code to implement ARB_texture_float extension is included
and can be toggled on at compile time, for those who purchased a
- license from SGI, or are in a country where the this patent do not
- apply, etc.
+ license from SGI, or are in a country where the patent does not apply,
+ etc.
The software is provided "as is", without warranty of any kind, express
or implied, including but not limited to the warranties of