verbs: Fix description of manual for ibv wc read byte len function

[ Upstream commit 7307264 ]

The ibv_wc_read_byte_len function is used to get the length of the payload
instead of vendor error.

Fixes: 10f97b6 ("Add member functions to poll an extended CQ")
Signed-off-by: Xinhao Liu <liuxinhao5@hisilicon.com>
Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Nicolas Morey-Chaisemartin <nmoreychaisemartin@suse.com>

libibverbs/man/ibv_create_cq_ex.3

@@ -106,7 +106,7 @@ Below members and functions are used in order to poll the current completion. Th
  Get the vendor error from the current completion.
 
 .BI "uint32_t ibv_wc_read_byte_len(struct ibv_cq_ex " "*cq"); \c
- Get the vendor error from the current completion.
+ Get the payload length from the current completion.
 
 .BI "__be32 ibv_wc_read_imm_data(struct ibv_cq_ex " "*cq"); \c
  Get the immediate data field from the current completion.