Fix typos in module/zfs/

Reviewed-by: Matt Ahrens <matt@delphix.com>
Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #9240

module/zfs/fm.c

@@ -31,7 +31,7 @@
  * Name-Value Pair Lists
  *
  * The embodiment of an FMA protocol element (event, fmri or authority) is a
- * name-value pair list (nvlist_t).  FMA-specific nvlist construtor and
+ * name-value pair list (nvlist_t).  FMA-specific nvlist constructor and
  * destructor functions, fm_nvlist_create() and fm_nvlist_destroy(), are used
  * to create an nvpair list using custom allocators.  Callers may choose to
  * allocate either from the kernel memory allocator, or from a preallocated
@@ -784,7 +784,7 @@ zfs_zevent_destroy(zfs_zevent_t *ze)
 #endif /* _KERNEL */
 
 /*
- * Wrapppers for FM nvlist allocators
+ * Wrappers for FM nvlist allocators
  */
 /* ARGSUSED */
 static void *