IB/core: Fix sparse warnings about redeclared functions

Fix a few functions that are declared with __attribute_const__ in the
ib_verbs.h header file but defined without it in verbs.c.  This gets rid
of the following sparse warnings:

    drivers/infiniband/core/verbs.c:51:5: error: symbol 'ib_rate_to_mult' redeclared with different type (originally declared at include/rdma/ib_verbs.h:469) - different modifiers
    drivers/infiniband/core/verbs.c:68:14: error: symbol 'mult_to_ib_rate' redeclared with different type (originally declared at include/rdma/ib_verbs.h:607) - different modifiers
    drivers/infiniband/core/verbs.c:85:5: error: symbol 'ib_rate_to_mbps' redeclared with different type (originally declared at include/rdma/ib_verbs.h:476) - different modifiers
    drivers/infiniband/core/verbs.c:111:1: error: symbol 'rdma_node_get_transport' redeclared with different type (originally declared at include/rdma/ib_verbs.h:84) - different modifiers

Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index acd8251..e9da1bc 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -80,8 +80,8 @@
 	RDMA_TRANSPORT_USNIC_UDP
 };
 
-enum rdma_transport_type
-rdma_node_get_transport(enum rdma_node_type node_type) __attribute_const__;
+__attribute_const__ enum rdma_transport_type
+rdma_node_get_transport(enum rdma_node_type node_type);
 
 enum rdma_link_layer {
 	IB_LINK_LAYER_UNSPECIFIED,
@@ -466,14 +466,14 @@
  * converted to 2, since 5 Gbit/sec is 2 * 2.5 Gbit/sec.
  * @rate: rate to convert.
  */
-int ib_rate_to_mult(enum ib_rate rate) __attribute_const__;
+__attribute_const__ int ib_rate_to_mult(enum ib_rate rate);
 
 /**
  * ib_rate_to_mbps - Convert the IB rate enum to Mbps.
  * For example, IB_RATE_2_5_GBPS will be converted to 2500.
  * @rate: rate to convert.
  */
-int ib_rate_to_mbps(enum ib_rate rate) __attribute_const__;
+__attribute_const__ int ib_rate_to_mbps(enum ib_rate rate);
 
 enum ib_mr_create_flags {
 	IB_MR_SIGNATURE_EN = 1,
@@ -604,7 +604,7 @@
  * enum.
  * @mult: multiple to convert.
  */
-enum ib_rate mult_to_ib_rate(int mult) __attribute_const__;
+__attribute_const__ enum ib_rate mult_to_ib_rate(int mult);
 
 struct ib_ah_attr {
 	struct ib_global_route	grh;