config.py: do not enable MBEDTLS_PLATFORM_GET_ENTROPY_ALT in full config

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/scripts/config.py b/scripts/config.py
index 3fc3614..6b30c54 100755
--- a/scripts/config.py
+++ b/scripts/config.py
@@ -123,6 +123,7 @@
     an implementation of the relevant functions and an xxx_alt.h header.
     """
     if name in (
+            'MBEDTLS_PLATFORM_GET_ENTROPY_ALT',
             'MBEDTLS_PLATFORM_GMTIME_R_ALT',
             'MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT',
             'MBEDTLS_PLATFORM_MS_TIME_ALT',