power: regulator: stm32: Fix warnings when compiling with W=1

This patch solves the following warnings:

drivers/power/regulator/stm32-vrefbuf.c: In function 'stm32_vrefbuf_set_value':
warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if (uV == stm32_vrefbuf_voltages[i]) {
          ^~

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
1 file changed