Various fixes for the RPM target (#684)

* prepare: always patch RPM mkspec

Like this we can notice earlier if it doesn't apply any longer
Otherwise I only test RPM when issues get openned

* RPM: fix RPM mkspecp atch, thanks @W3sG for the heads up!

- Only part of the patch was applying
- Fixed also the fact that packages conflict because of
  unneeded build-id files in /usr/lib/.build-id
- Removed all the hardening flags Fedora uses by default
  "we do not do that here"

Fixes: #669 #609

* install.sh: uninstall-help: fix Fedora query for installed TKG packages

* install.sh: RPM: fix typo in variable

Used the non absolute path for the work folder x)

install.sh

@@ -249,7 +249,7 @@ if [ "$1" = "install" ]; then
       _extra_ver_str="_${_kernel_flavor}"
     fi
 
-    _fedora_work_dir="$_kernel_work_folder/linux-tkg-rpmbuild"
+    _fedora_work_dir="$_kernel_work_folder_abs/linux-tkg-rpmbuild"
 
     msg2 "Building kernel RPM packages"
     RPMOPTS="--define '_topdir ${_fedora_work_dir}'" make ${llvm_opt} -j ${_thread_num} rpm-pkg EXTRAVERSION="${_extra_ver_str}"
@@ -416,7 +416,7 @@ if [ "$1" = "uninstall-help" ]; then
     msg2 "Note: linux-libc-dev packages are no longer created and installed, you can safely remove any remnants."
   elif [ "$_distro" = "Fedora" ]; then
     msg2 "List of installed custom tkg kernels: "
-    dnf list --installed kernel*
+    dnf list --installed | grep -i "tkg"
     msg2 "To uninstall a version, you should remove the kernel, kernel-headers and kernel-devel associated to it (if installed), with: "
     msg2 "      sudo dnf remove --noautoremove kernel-VERSION kernel-devel-VERSION kernel-headers-VERSION"
     msg2 "       where VERSION is displayed in the second column"