This warning was issued by cppcheck in our downstream code:
[plat/st/common/stm32mp_dt.c:629] -> [plat/st/common/stm32mp_dt.c:634]:
 (warning) Identical condition 'node<0', second condition is always false

The second test has to check variable pwr_regulators_node.

Change-Id: I4a20c4a3ac0ef0639c2df36309d90a61c02b511f
Signed-off-by: Yann Gautier <yann.gautier@st.com>