fix(mmc): explicitly check operators precedence

This corrects the MISRA violation C2012-12.1:
The precedence of operators within expressions should be made explicit
While at it put the test on one line.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: Id19231faaf033c1e7dbe703690e0dddc7aa8f346
1 file changed