doc: fix typo in coding style

[ upstream commit 6965091 ]

This patch fixes a typo in DPDK Coding Style, in Return Values section,
i.e. replaces "indicated may" with "indicated by".

Fixes: 36032e4 ("doc: add coding style")

Signed-off-by: Dariusz Sosnowski <dsosnowski@nvidia.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>

doc/guides/contributing/coding_style.rst

@@ -591,7 +591,7 @@ Return Value
 ~~~~~~~~~~~~
 
 * Functions which create objects, or allocate memory, should return pointer types, and NULL on error.
-  The error type should be indicated may setting the variable ``rte_errno`` appropriately.
+  The error type should be indicated by setting the variable ``rte_errno`` appropriately.
 * Functions which work on bursts of packets, such as RX-like or TX-like functions, should return the number of packets handled.
 * Other functions returning int should generally behave like system calls:
   returning 0 on success and -1 on error, setting ``rte_errno`` to indicate the specific type of error.