Initial riscv64 support

Most of the changes are self-explanatory and just follow what's
already happening for existing architectures.

Two things are worth pointing out:

  * we need to use shim-unsigned instead of shim-signed because
    riscv64 is not fully integrated into Fedora yet and so we
    can't do Secure Boot signing for the time being;

  * we use ext4 as bootfilesystem since in most cases the
    underlying firmware is going to be U-Boot, which needs to be
    able to load the board's DTB from /boot and doesn't support
    XFS.

Signed-off-by: David Abdurachmanov <davidlt@rivosinc.com>

components/boot.xml

@@ -7,7 +7,7 @@
 			<requires profile="BootCore"/>
 		</profile>
 	</profiles>
-	<preferences profiles="BootDiskCore" arch="x86_64">
+	<preferences profiles="BootDiskCore" arch="x86_64,riscv64">
 		<type image="oem"
 		      filesystem="btrfs" btrfs_root_is_subvolume="true" btrfs_set_default_volume="false" fsmountoptions="x-systemd.growfs,compress=zstd:1"
 		      kernelcmdline="rhgb quiet" devicepersistency="by-uuid"
@@ -86,6 +86,8 @@
 	<packages type="image" patternType="plusRecommended" profiles="BootCore">
 		<package name="grub2-efi-aa64" arch="aarch64"/>
 		<package name="grub2-efi-aa64-modules" arch="aarch64"/>
+		<package name="grub2-efi-riscv64" arch="riscv64"/>
+		<package name="grub2-efi-riscv64-modules" arch="riscv64"/>
 		<package name="grub2-efi-x64" arch="x86_64"/>
 		<package name="grub2-efi-x64-modules" arch="x86_64"/>
 		<package name="grub2-pc" arch="x86_64"/>
@@ -94,6 +96,7 @@
 		<package name="s390utils-base" arch="s390x"/>
 		<package name="shim-signed-aa64" arch="aarch64"/>
 		<package name="shim-signed-x64" arch="x86_64"/>
+		<package name="shim-unsigned-riscv64" arch="riscv64"/>
 		<package name="kernel-core"/>
 		<package name="systemd-oomd-defaults"/>
 		<package name="systemd-resolved"/>
@@ -101,6 +104,7 @@
 	<packages type="image" patternType="plusRecommended" profiles="BootCoreUKI">
 		<package name="shim-signed-aa64" arch="aarch64"/>
 		<package name="shim-signed-x64" arch="x86_64"/>
+		<package name="shim-unsigned-riscv64" arch="riscv64"/>
 		<package name="systemd-oomd-defaults"/>
 		<package name="systemd-resolved"/>
 		<package name="kernel-uki-virt"/>
@@ -109,6 +113,7 @@
 	</packages>
 	<packages type="iso" patternType="plusRecommended" profiles="BootCore">
 		<package name="grub2-efi-aa64-cdboot" arch="aarch64"/>
+		<package name="grub2-efi-riscv64-cdboot" arch="riscv64"/>
 		<package name="grub2-efi-x64-cdboot" arch="x86_64"/>
 	</packages>
 	<packages type="image" patternType="plusRecommended" profiles="BootDiskCore">
@@ -121,5 +126,6 @@
 		<package name="btrfs-progs"/>
 		<package name="udisks2-btrfs"/>
 		<package name="uboot-images-armv8" arch="aarch64"/>
+		<package name="uboot-images-riscv64" arch="riscv64"/>
 	</packages>
 </image>