libgnt/libgnt

Fix a few documentation issues

2021-07-23, Gary Kramlich
d8762e1bb08e
Fix a few documentation issues

Testing Done:
ran `ninja libgnt-doc`

Reviewed at https://reviews.imfreedom.org/r/824/
option('doc', type : 'boolean', value : true, yield : true,
description : 'build documentation with gtk-doc')
option('introspection', type : 'boolean', value : true, yield : true,
description : 'build introspection data')