Doc: Typos in documentation

No semantic changes.  The next patch in this series will
do the actual changes to sync with NTP current
best practices

Signed-off-by: Sanjeev Gupta <ghane0@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/Documentation/pps/pps.txt b/Documentation/pps/pps.txt
index a15a116..a9f53bb 100644
--- a/Documentation/pps/pps.txt
+++ b/Documentation/pps/pps.txt
@@ -63,7 +63,7 @@
 possibility to open another device as PPS source.
 
 In LinuxPPS the PPS sources are simply char devices usually mapped
-into files /dev/pps0, /dev/pps1, etc..
+into files /dev/pps0, /dev/pps1, etc.
 
 
 PPS with USB to serial devices
@@ -71,7 +71,7 @@
 
 It is possible to grab the PPS from an USB to serial device. However,
 you should take into account the latencies and jitter introduced by
-the USB stack. Users has reported clock instability around +-1ms when
+the USB stack. Users have reported clock instability around +-1ms when
 synchronized with PPS through USB. This isn't suited for time server
 synchronization.