Added mb styles feature to 'p2-profile' pom. Replaced main.css file content with 2.2.0.

The following request would fix the MB admin panel UI which would remove the carbon log and etc that is currently appearing. 
The request consist of 2 fixes.
1. Added the mb style feature to 'p2-profile' pom. 
2. The main.css(product-mb/modules/styles/product/src/main/resources/web/styles/css/main.css) file content was replaced with the content of main.css in 2.2.0.