kernel-doc: single DOC: selection
kernel-doc: single DOC: selection

Currently, DOC: sections are always output even if only a single
function is requested, fix this and also make it possible to just
output a single DOC: section by giving its title as the function
name to output.

Also fixes docbook XML well-formedness for sections with examples.

Signed-off-by: Johannes Berg <8398eb9892c5ab2ff439ca0b5e4b0706dd9ebef9@sipsolutions.net>
Signed-off-by: Randy Dunlap <e1d10faa7e2a0c027bf1ff1d20e7fd10154be7ea@oracle.com>
Signed-off-by: Sam Ravnborg <f16bed56189e249fe4ca8ed10a1ecae60e8ceac0@ravnborg.org>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs