Fix spurious trailing whitespace in comment

Author: martin-frbg

kernel/power/strmm_kernel_16x8_power8.S

@@ -12,7 +12,7 @@ the documentation and/or other materials provided with the
 distribution.
 3. Neither the name of the OpenBLAS project nor the names of
 its contributors may be used to endorse or promote products
-derived from this software without specific prior written permission.  
+derived from this software without specific prior written permission.
 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE