kernel-doc: extend $type_param to match members referenced by pointer

Currently, function parameter description can match '@type.member'
expressions but fails to match '@type->member'.
Extend the $type_param regex to allow matching both
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

scripts/kernel-doc

@@ -212,7 +212,7 @@ my $anon_struct_union = 0;
 my $type_constant = '\b``([^\`]+)``\b';
 my $type_constant2 = '\%([-_\w]+)';
 my $type_func = '(\w+)\(\)';
-my $type_param = '\@(\w*(\.\w+)*(\.\.\.)?)';
+my $type_param = '\@(\w*((\.\w+)|(->\w+))*(\.\.\.)?)';
 my $type_fp_param = '\@(\w+)\(\)';  # Special RST handling for func ptr params
 my $type_env = '(\$\w+)';
 my $type_enum = '\&(enum\s*([_\w]+))';