staging: rtl8723bs: hal: move common code to macro

In halbtc8723b2ant_TdmaDurationAdjust function,below piece of code is
repeated many times.

halbtc8723b2ant_PsTdma(pBtCoexist, NORMAL_EXEC, true, val);
pCoexDm->psTdmaDuAdjType = val;

So replace the same with "HAL_BTC8723B2ANT_DMA_DURATION_ADJUST" MACRO.
Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com>
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changes in v2: clean the changelog with proper indent
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Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>