Update docs/proposals/20190919-machinepool-api.md

Co-authored-by: Jason DeTiberus <[email protected]>

Author: fiunchinho

docs/proposals/20190919-machinepool-api.md

@@ -168,8 +168,7 @@ type MachinePoolSpec struct
     - Description: Name of the Cluster this machine pool belongs to.
   - **FailureDomains [optional]**
     - Type: `[]string`
-    - Description: FailureDomainSpec is the Schema for Cluster API failure domains.
-      It allows controllers to understand how many failure domains a cluster can optionally span across.
+    - Description: FailureDomains is the list of failure domains this MachinePool should be attached to.
   - **Replicas [optional]**
     - Type: `*int32`
     - Description: Number of desired machine instances. Defaults to 1.
@@ -419,4 +418,3 @@ inconsistent experience across providers.
 10/23/2019: First round of feedback from community
 10/23/2019: Present proposal at a community meeting
 10/31/2019: Open proposal PR
-