samples: cellular: http_update: Prevalidate modem firmware

Prevalidation of the modem firmware has been supported since 1.3.0.
There is no need to skip it here.

Signed-off-by: Markus Rekdal <[email protected]>

Author: nordic-mare

samples/cellular/http_update/modem_full_update/prj.conf

@@ -83,6 +83,3 @@ CONFIG_MBEDTLS_GCM_C=n
 CONFIG_MBEDTLS_SHA256_C=y
 
 CONFIG_DOWNLOAD_HOST="nrfconnectsdk.s3.eu-central-1.amazonaws.com"
-
-# Prevalidation is not yet supported by the modem firmware, so skip it for now.
-CONFIG_FMFU_FDEV_SKIP_PREVALIDATION=y