receiptomatic-www: common.h: Small coding clean up
receiptomatic-www: common.h: Small coding clean up

Make the session structure definition match the others and remove an
excess blank line.

Signed-off-by: Andrew Clayton <02e0a999c50b1f88df7a8f5a04e1b76b35ea6a88@opentechlabs.co.uk>

ac000/receiptomatic