rpm: hotfix - disable automatic setting of hardening flags

New Fedora distributions add additional hardening flags to compiler and
linker etc. by default in rpmbuild.
However, this change breaks configure checks and the build process fails
with:

```
configure: error: in `/builddir/build/BUILD/ipfixprobe-4.7.1':
configure: error: cannot run C compiled programs.
If you meant to cross compile, use `--host'.
See `config.log' for more details
```

The cause is probably:
`LDFLAGS=-specs=/usr/lib/rpm/redhat/redhat-hardened-ld`

when this particular flag is removed, the build (and configure works).

This patch is considered a temporary solution to build new package.
The situation should be investigated in more details.

Author: cejkato2

ipfixprobe.spec.in

@@ -41,6 +41,11 @@
 %global is_el7 no
 %endif
 
+# Hotfix to allow RPM build on fedora36+
+# There is a problem in configure autodetection when
+# LDFLAGS=-specs=/usr/lib/rpm/redhat/redhat-hardened-ld
+%undefine _auto_set_build_flags
+
 Name: ipfixprobe
 Version: @PACKAGE_VERSION@
 Release: @RELEASE@