templates: Add Debian and Fedora riscv64 images

The Debian image is the latest from unstable as there's no release yet
for riscv64.

The Fedora 41 and 42 cloud images hosted at the 'alt' location. It's not
clear how often this will be updated, so the URL may become stale at
some point.

Signed-off-by: Joel Stanley <[email protected]>

Author: shenki

templates/_images/fedora-41.yaml

@@ -7,6 +7,10 @@ images:
   arch: aarch64
   digest: sha256:085883b42c7e3b980e366a1fe006cd0ff15877f7e6e984426f3c6c67c7cc2faa
 
+- location: https://dl.fedoraproject.org/pub/alt/risc-v/release/41/Cloud/riscv64/images/Fedora-Cloud-Base-Generic-41.20250224-1026a2d0e311.riscv64.qcow2
+  arch: riscv64
+  digest: sha256:6a8272a858d7f1498f49ce362b34f0b9b959885f63285158947e045abfeece40
+
 # 9p is broken in Linux v6.9, v6.10, and v6.11 (used by Fedora 41).
 # The issue was fixed in Linux v6.12-rc5 (https://github.com/torvalds/linux/commit/be2ca38).
 mountTypesUnsupported: [9p]

templates/_images/fedora-42.yaml

@@ -7,6 +7,9 @@ images:
   arch: aarch64
   digest: sha256:e10658419a8d50231037dc781c3155aa94180a8c7a74e5cac2a6b09eaa9342b7
 
+- location: https://dl.fedoraproject.org/pub/alt/risc-v/release/42/Cloud/riscv64/images/Fedora-Cloud-Base-Generic-42.20250414-8635a3a5bfcd.riscv64.qcow2
+  arch: riscv64
+  digest: sha256:537c67710f4f1c9112fecaafafc293b649acd1d35b46619b97b5a5a0132241b0
 
 # # NOTE: Intel Mac requires setting vmType to qemu
 # # https://github.com/lima-vm/lima/issues/3334

templates/experimental/debian-sid.yaml

@@ -9,4 +9,7 @@ images:
 - location: https://cloud.debian.org/images/cloud/sid/daily/latest/debian-sid-genericcloud-arm64-daily.qcow2
   arch: aarch64
 
+- location: https://cloud.debian.org/images/cloud/sid/daily/latest/debian-sid-genericcloud-riscv64-daily.qcow2
+  arch: riscv64
+
 mountTypesUnsupported: [9p]