mesa: Return error if BeginQuery is called with an existing object of different type

mesa: Return error if BeginQuery is called with an existing object of different type

Section 2.14 Asynchronous Queries, page 84 of the OpenGL ES 3.0.4
spec states:

  "BeginQuery generates an INVALID_OPERATION error if any of the
   following conditions hold: [...] id is the name of an
   existing query object whose type does not match target; [...]

Similar wording exists in the OpenGL 4.5 spec, section 4.2. QUERY
OBJECTS AND ASYNCHRONOUS QUERIES, page 43.

Fixes 1 dEQP test:
* dEQP-GLES3.functional.negative_api.fragment.begin_query

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>