vn_fullpath.9: Fix two typos in the manual page

- s/resulting/resulting/
- s/initally/initially/

MFC after:	5 days

share/man/man9/vn_fullpath.9

@@ -107,7 +107,7 @@ than one name (hard links), not all file systems use the name cache
 be used for more than one file (in the context of file systems covering
 other file systems); a file may have no name (if deleted but still
 open or referenced).
-However, the resulting string may still be more useable to a user than
+However, the resulting string may still be more usable to a user than
 a vnode pointer value, or a device number and inode number.
 Code consuming the results of this function should anticipate (and
 properly handle) failure.
@@ -187,7 +187,7 @@ otherwise, an error number is returned.
 .Xr free 9
 .Sh AUTHORS
 .An -nosplit
-This manual page was initally written by
+This manual page was initially written by
 .An Robert Watson Aq Mt [email protected]
 to describe the
 .Fn vn_fullpath