docs for ceph: fix typo

docs/20_Checks/check_ceph_diskfree.md

@@ -2,7 +2,7 @@
 
 ## Introduction
 
-**check_cehp_diskfree** is a plugin to show the available and free diskspace.
+**check_ceph_diskfree** is a plugin to show the available and free diskspace.
 It returns a single line for the status, data and performance data.
 
 ## Requirements

docs/20_Checks/check_ceph_io.md

@@ -2,7 +2,7 @@
 
 ## Introduction
 
-**check_cehp_io** is a plugin to show read and written bytes per second. 
+**check_ceph_io** is a plugin to show read and written bytes per second. 
 It returns a single line for the status and performance data.
 
 ## Requirements