lib: utils_def: add CLAMP macro

Add the standard CLAMP macro.  It ensures that
x is between the limits set by low and high.
If low is greater than high the result is undefined.

Signed-off-by: Lionel Debieve <lionel.debieve@st.com>
Change-Id: Ia173bb9ca51bc8d9a8ec573bbc15636a94f881f4
1 file changed