update README.md

removed section of creating an IAM as you have to manually add the policies to the auto-generated Lambda IAM role.

Author: stroupaloop

README.md

@@ -17,8 +17,7 @@ Step-by-step on how to configure, develop & deploy this app on AWS.
 2. Pick a region in the console and be consistent throughout this app. Use either `us-east-1`, `us-west-2` & `eu-west-1`. 
 3. Create a table in DynamoDB with a single Hash named `fromNumber` for primary key of type String. We don't need any additional indexes and you can keep the read/write capacity at 1 for this example.
 4. Create an S3 bucket to ingest MMS images. 
-5. Create an IAM role with access to the S3 bucket & the DynamoDB table.
-6. Create/login to a Twilio account & create a phone number with MMS capability. 
+5. Create/login to a Twilio account & create a phone number with MMS capability. 
 
 ### *NEW* Serverless Application Model (SAM) Deployment