docs: conf.py: adjust the LaTeX document output

Changeset f546ff0c0c ("Move our minimum Sphinx version to 1.7")
cleaned up some compatibility issues with previous Sphinx
versions, but it also dropped the PDF margin sets.

Without that, the media documentation won't build fine, as
the margins are too wide to display texts with monospaced
fonts.

While here, align the  "latex_elements = {" values, and add
a few other sphinxsetup configs in order to allow Sphinx to
wrap long lines on literal blocks.

Fixes: f546ff0c0c ("Move our minimum Sphinx version to 1.7")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

 Documentation/conf.py | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)
Link: https://lore.kernel.org/r/911fbac185dd09c7df715cf4153361b81f04b7ad.1614787053.git.mchehab+huawei@kernel.org

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/conf.py

@@ -331,27 +331,34 @@ htmlhelp_basename = 'TheLinuxKerneldoc'
 # -- Options for LaTeX output ---------------------------------------------
 
 latex_elements = {
-# The paper size ('letterpaper' or 'a4paper').
-'papersize': 'a4paper',
+    # The paper size ('letterpaper' or 'a4paper').
+    'papersize': 'a4paper',
 
-# The font size ('10pt', '11pt' or '12pt').
-'pointsize': '11pt',
+    # The font size ('10pt', '11pt' or '12pt').
+    'pointsize': '11pt',
 
-# Latex figure (float) alignment
-#'figure_align': 'htbp',
+    # Latex figure (float) alignment
+    #'figure_align': 'htbp',
 
-# Don't mangle with UTF-8 chars
-'inputenc': '',
-'utf8extra': '',
+    # Don't mangle with UTF-8 chars
+    'inputenc': '',
+    'utf8extra': '',
 
-# Additional stuff for the LaTeX preamble.
+    # Set document margins
+    'sphinxsetup': '''
+        hmargin=0.5in, vmargin=1in,
+        parsedliteralwraps=true,
+        verbatimhintsturnover=false,
+    ''',
+
+    # Additional stuff for the LaTeX preamble.
     'preamble': '''
-	% Use some font with UTF-8 support with XeLaTeX
+        % Use some font with UTF-8 support with XeLaTeX
         \\usepackage{fontspec}
         \\setsansfont{DejaVu Sans}
         \\setromanfont{DejaVu Serif}
         \\setmonofont{DejaVu Sans Mono}
-     '''
+     ''',
 }
 
 # At least one book (translations) may have Asian characters