Unable to access SSRS web URL outside Azure VM
Your URL is wrong and also you can configure the firewall. Try below URL.  Configure port as describe below if you have not already.  

http://jarvissqlvm.cloudapp.net/ReportServer/PageTo Connect to Remote Report Manager


Here are more detail steps.

Reference: 

https://web.archive.org/web/20140523110804/http://msdn.microsoft.com/en-us/library/azure/jj992719.aspx


  If you want to connect to Report Manager on the virtual machine from a
  remote computer, create a new virtual machine TCP Endpoint. By
  default, the report server listens for HTTP requests on port 80. If
  you configure the report server URLs to use a different port, you must
  specify that port number in the following instructions. Create an
  Endpoint for the Virtual Machine of TCP Port 80. For more information
  see, the Virtual Machine Endpoints and Firewall Ports section in this
  document.
  
  Open port 80 in the virtual machine’s firewall.
  
  Browse to report manager using Azure Virtual Machine DNS Name as the
  server name in the URL. For example: 
  
  Report manager:http://uebi.cloudapp.net/reportserver
  
  Report server:http://uebi.cloudapp.net/reports
  
  Configure a Firewall for Report Server Access
  (http://technet.microsoft.com/en-us/library/bb934283.aspx).