xia: style fixes for comments throughout code

This patch complies with patches:
  - 058806007450489bb8f457b275e5cb5c946320c1
    checkpatch: check networking specific block comment style
  - a605e32ebde25dc31f943fecb30e3e28079ccd06
    checkpatch: warn when networking block comment lines don't start with *

Fixed block commenting issues raised by scripts/checkpatch.pl. Ignored
warnings when an empty /* line is appropriate for defining a section
of code in a file, or when used for commenting out large chunks of
code.

Also fixed some comment spacing, punctuation, and spelling.
xia: style fixes for variable declarations

This patch complies with patch:
  - 3b617e3b80548096eda92ebd8382f76b139e011c
    checkpatch: net and drivers/net: warn on missing blank line after ...

Changed variable declarations so that there is a blank line separating
them with other code. Ignored the warning for better readability when
blocks of code (excluding declarations) was only one line.
xia: style fixes for curly braces

This patch complies with patch:
  - aad4f61498314d41d047ea2161b7bd7237b72d33
    checkpatch: add --strict tests for braces, comments and casts
xia: style fixes for space around casts

This patch complies with patch:
  - aad4f61498314d41d047ea2161b7bd7237b72d33
    checkpatch: add --strict tests for braces, comments and casts

Ignored warnings that are false positives using the sizeof operator.