spec: Advertise nvram paths of official fedora edk2 builds

Fedora now ships edk2 firmware in its official repos, so adapt
the nvram path list to match. Eventually we can remove the nightly
links as well once some integration kinks have been worked out,
and documentation updated.

Move the macro building into the %build target, which lets us
build up a shell variable and make things a bit more readable

https://bugzilla.redhat.com/show_bug.cgi?id=1335395
(cherry picked from commit e9ef4dfa)

libvirt.spec.in

@@ -344,20 +344,6 @@
 %endif
 
 
-# Advertise OVMF and AAVMF from nightly firmware repo
-%if 0%{?fedora}
-    %define with_loader_nvram --with-loader-nvram="/usr/share/edk2.git/ovmf-x64/OVMF_CODE-pure-efi.fd:/usr/share/edk2.git/ovmf-x64/OVMF_VARS-pure-efi.fd:/usr/share/edk2.git/aarch64/QEMU_EFI-pflash.raw:/usr/share/edk2.git/aarch64/vars-template-pflash.raw"
-%endif
-
-
-# The RHEL-5 Xen package has some feature backports. This
-# flag is set to enable use of those special bits on RHEL-5
-%if 0%{?rhel} == 5
-    %define with_rhel5  1
-%else
-    %define with_rhel5  0
-%endif
-
 %if 0%{?fedora} >= 18 || 0%{?rhel} >= 7
     %define with_systemd_macros 1
 %else
@@ -1470,6 +1456,18 @@ rm -rf .git
     %endif
 %endif
 
+%if 0%{?fedora}
+    # Nightly firmware repo x86/OVMF
+    LOADERS="/usr/share/edk2.git/ovmf-x64/OVMF_CODE-pure-efi.fd:/usr/share/edk2.git/ovmf-x64/OVMF_VARS-pure-efi.fd"
+    # Nightly firmware repo aarch64/AAVMF
+    LOADERS="$LOADERS:/usr/share/edk2.git/aarch64/QEMU_EFI-pflash.raw:/usr/share/edk2.git/aarch64/vars-template-pflash.raw"
+    # Fedora official x86/OVMF
+    LOADERS="$LOADERS:/usr/share/edk2/ovmf/OVMF_CODE.fd:/usr/share/edk2/ovmf/OVMF_VARS.fd"
+    # Fedora official aarch64/AAVMF
+    LOADERS="$LOADERS:/usr/share/edk2/aarch64/QEMU_EFI-pflash.raw:/usr/share/edk2/aarch64/vars-template-pflash.raw"
+    %define with_loader_nvram --with-loader-nvram="$LOADERS"
+%endif
+
 # place macros above and build commands below this comment
 
 %if 0%{?enable_autotools}