Add missing Javadoc dependency to `com.android.location.provider`

The `LocationProviderBase.java` file imports
`android.location.provider.ProviderRequest` and references it from
the Javadoc of the `onSetReqeust(...)` method.

Strictly speaking, that class should have been imported in the stubs
to ensure that the references in the Javadoc could be correctly
resolved. However, due to some inaccurate handling of imports in
Metalava the import was not added to the stubs.

The handling of imports in Metalava will be improved and so the class
will be correctly imported. However, that would lead to a compile time
failure because `ProviderRequest` is not on the classpath when
compiling the stubs. This change avoids that by adding the missing
dependency in preparation for the Metalava changes.

Bug: 371955471
Test: m droid
Change-Id: If523d495f9822e8b1ac011442564407454080a7b