fix(plat/st): correct signedness comparison issue

Add casts where required to avoid compialtion error when enabling
-Wsign-compare in shared resources file.
The assert is also corrected to match the correct range (change ||
to &&).

Change-Id: Ie4c9c0c935d39ff9a2165b909172aacb3e94ab4d
Signed-off-by: Yann Gautier <yann.gautier@st.com>
1 file changed