gpio: stm32_gpio: Fix warnings when compiling with W=1

This patch solves the following warnings:

drivers/gpio/stm32_gpio.c: In function 'stm32_offset_to_index':
: comparison between signed and unsigned integer expressions [-Wsign-compare]
    if (idx == offset)
            ^~
Signed-off-by: Patrice Chotard <patrice.chotard@st.com>

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