Fix some signedness warnings on threaded builds introduced by r12369

This commit was SVN r12376.

The following SVN revision numbers were found above:
  r12369 --> open-mpi/ompi@d7375ec102

ompi/mca/btl/openib/btl_openib.h

@@ -120,7 +120,7 @@ struct mca_btl_openib_component_t {
     uint32_t use_eager_rdma;
     int32_t eager_rdma_threshold;
     uint32_t eager_rdma_num;
-    uint32_t max_eager_rdma;
+    int32_t max_eager_rdma;
     uint32_t btls_per_lid;
     uint32_t max_lmc;
     uint32_t buffer_alignment;
@@ -203,7 +203,7 @@ struct mca_btl_openib_module_t {
 
     size_t eager_rdma_frag_size; /**< length of eager frag */
     orte_pointer_array_t *eager_rdma_buffers; /**< RDMA buffers to poll */
-    volatile uint32_t eager_rdma_buffers_count; /**< number of RDMA buffers */
+    volatile int32_t eager_rdma_buffers_count; /**< number of RDMA buffers */
 
     mca_btl_base_module_error_cb_fn_t error_cb; /**< error handler */
    

ompi/mca/btl/openib/btl_openib_mca.c

@@ -311,7 +311,7 @@ int btl_openib_register_mca_params(void)
                   "with the \"dr\" pml) "
                   "(must be >= 0)",
                   16, &ival, REGINT_GE_ZERO));
-    mca_btl_openib_component.max_eager_rdma = (uint32_t) ival;
+    mca_btl_openib_component.max_eager_rdma = (int32_t) ival;
 
     CHECK(reg_int("eager_rdma_num", "Number of RDMA buffers to allocate "
                   "for small messages"