apparmor: Fix some kernel-doc comments

Add the description of @ns_name, change function name aa_u16_chunck to
unpack_u16_chunk and verify_head to verify_header in kernel-doc comment
to remove warnings found by running scripts/kernel-doc, which is caused
by using 'make W=1'.

security/apparmor/policy_unpack.c:224: warning: expecting prototype for
aa_u16_chunck(). Prototype was for unpack_u16_chunk() instead
security/apparmor/policy_unpack.c:678: warning: Function parameter or
member 'ns_name' not described in 'unpack_profile'
security/apparmor/policy_unpack.c:950: warning: expecting prototype for
verify_head(). Prototype was for verify_header() instead
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

security/apparmor/policy_unpack.c

@@ -214,7 +214,7 @@ static void *kvmemdup(const void *src, size_t len)
 }
 
 /**
- * aa_u16_chunck - test and do bounds checking for a u16 size based chunk
+ * unpack_u16_chunk - test and do bounds checking for a u16 size based chunk
  * @e: serialized data read head (NOT NULL)
  * @chunk: start address for chunk of data (NOT NULL)
  *
@@ -671,6 +671,7 @@ static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
 /**
  * unpack_profile - unpack a serialized profile
  * @e: serialized data extent information (NOT NULL)
+ * @ns_name: pointer of newly allocated copy of %NULL in case of error
  *
  * NOTE: unpack profile sets audit struct if there is a failure
  */
@@ -939,7 +940,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 }
 
 /**
- * verify_head - unpack serialized stream header
+ * verify_header - unpack serialized stream header
  * @e: serialized data read head (NOT NULL)
  * @required: whether the header is required or optional
  * @ns: Returns - namespace if one is specified else NULL (NOT NULL)