doc: CSS tweak for table caption location

Default behavior is for figure captions below the figure, but table
captions above the table.  Tweak the CSS for tables to put the caption
below instead.

Signed-off-by: David B. Kinder <david.b.kinder@intel.com>

Author: dbkinder

doc/static/acrn-custom.css

@@ -91,6 +91,11 @@ table.align-center {
    display: table !important;
 }
 
+/* put the table caption at the bottom, as done for figures */
+table {
+   caption-side: bottom;
+}
+
 
 .code-block-caption {
     color: #000;