cubietech-cubieboard: use initramfs as initrd name (MR 3370)

boot-deploy renames initramfs-edge to initramfs.

Similar to https://gitlab.com/postmarketOS/pmaports/-/merge_requests/2521

device/testing/device-cubietech-cubieboard/APKBUILD

 # Reference: <https://postmarketos.org/devicepkg>
 pkgname=device-cubietech-cubieboard
 pkgdesc="Cubietech Cubieboard"
-pkgver=0.1
-pkgrel=6
+pkgver=0.1.1
+pkgrel=0
 url="https://postmarketos.org"
 license="MIT"
 arch="armv7"
@@ -28,5 +28,5 @@ package() {
 
 sha512sums="
 b83f061da45a453a9dc13d0c2396bbc7980008a8dd04d8611a287737d90c11e7854203dbce91e6f51eb5da370703ba01865e397f10c03b662b41ada127cb7334  deviceinfo
-a33dd1a89548eb95d95e07a879bf412985bd01ebfef8e2ddaaa5c3e2d173743c3530148e36a9fc81a07e67b4a35509f06852bd2f652f64a9b6224ce8d7e12d56  extlinux.conf
+1e6e94ae7115af82ada2131ef59cba82a00933e65f7c04482bc714a7d117a6700de9e3254b98405e3d07c489883f073443aa1390ed026717afe3642b6b09e268  extlinux.conf
 "

device/testing/device-cubietech-cubieboard/extlinux.conf

@@ -6,4 +6,4 @@ label POSTMARKETOS
   linux /vmlinuz-edge
   append console=ttyS0,115200n8 PMOS_NO_OUTPUT_REDIRECT
   fdtdir /dtbs-edge
-  initrd /initramfs-edge
+  initrd /initramfs