[CARBONDATA-1892]updated documentation for disability of single_pass on first load
[CARBONDATA-1892]updated documentation for disability of single_pass on first load

Correction In the documentation of single_pass is required as now single_pass is not disabled for the first load

This closes #1652

jackylk/incubator-carbondata,zzcclp/carbondata,jackylk/incubator-carbondata,zzcclp/carbondata,zzcclp/carbondata,sgururajshetty/carbondata,manishgupta88/incubator-carbondata,jackylk/incubator-carbondata,sgururajshetty/carbondata,manishgupta88/carbondata,manishgupta88/carbondata,jatin9896/incubator-carbondata,jackylk/incubator-carbondata,sgururajshetty/carbondata,zzcclp/carbondata,zzcclp/carbondata,jatin9896/incubator-carbondata,jatin9896/incubator-carbondata,manishgupta88/carbondata,ravipesala/incubator-carbondata,manishgupta88/incubator-carbondata,manishgupta88/carbondata,ravipesala/incubator-carbondata,ravipesala/incubator-carbondata,manishgupta88/incubator-carbondata,ravipesala/incubator-carbondata,manishgupta88/incubator-carbondata