fix(st-regulator): rework for_each_*rdev macros

This corrects MISRA C2012-18.4:
The +, -, += and -= operators should not be applied to an expression
of pointer type.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: Ie1a196b875eae2eff9242cf83abfc1a79bdee6f3
1 file changed