install-wolfprov.sh: Pass WOLFPROV_DEBUG through to dpkg-buildpackage

Without -eWOLFPROV_DEBUG, the debug flag was not visible to debian/rules
during package build, so debug variants were never produced.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ColtonWilley

debian/install-wolfprov.sh

@@ -100,6 +100,7 @@ wolfprov_build() {
     WOLFSSL_ISFIPS=${WOLFSSL_ISFIPS:-0}
     dpkg-buildpackage -us -uc \
     -eWOLFSSL_ISFIPS \
+    -eWOLFPROV_DEBUG \
     -eCC -eCXX \
     -eCCACHE_DIR -eCCACHE_BASEDIR -eCCACHE_NOHASHDIR -eCCACHE_COMPILERCHECK