[INTERNAL][FIX] sap.m.Input - screen reader adjustments
[INTERNAL][FIX] sap.m.Input - screen reader adjustments

- screen reader should announce the selected item number
  and the number of items in the suggestions list


Change-Id: Icf2d0e2f04e3d54e843e6978d34f2d103438d772
BCP: 1570860464

cschuff/openui5,SAP/openui5,olirogers/openui5,SQCLabs/openui5,SAP/openui5,cschuff/openui5,SQCLabs/openui5,olirogers/openui5,nzamani/openui5,nzamani/openui5,SAP/openui5,SAP/openui5,cschuff/openui5,nzamani/openui5,olirogers/openui5,SQCLabs/openui5