[Content] Removed deprecated storageType API usage

[Content] Removed deprecated storageType API usage

This commit removes all platform code related to storageType and
provides only a hardcoded 'storageType_NOT_SUPPORTED' value for easier
analysis of possible issues after removal.

[ACR] https://code.sec.samsung.net/jira/browse/TWDAPI-289

[Verification]

2 failing content TCTs which uses removed API, need to be
removedi/modified not to check storage type:
error:
invalid enum value value "storageType_NOT_SUPPORTED" not in array ["INTERNAL", "EXTERNAL"]
- ContentChangeCallback_oncontentdiradded
- ContentChangeCallback_oncontentdirupdated

1 deprecated TCT need to be removed:
- ContentDirectory_storageType_attribute

Change-Id: I0cf883097ce47c342949346a3fffca7f525faee8