Increase default boot.iso (uncompressed) fs size to 3gb.

We are now seeing aarch64 and x86_64 failures with the default 2gb.
Ideally one of the minimzation efforts could help us here.

Signed-off-by: Kevin Fenzi <kevin@scrye.com>

fedora.conf

@@ -103,17 +103,15 @@ buildinstall_skip = [
 
 # Enables macboot on x86_64 for all variants and disables upgrade image building
 # everywhere.
-# Use 3GB image size for ppc64le.
+# Use 3GB image size for all arches.
 lorax_options = [
   ('^.*$', {
      'x86_64': {
          'nomacboot': False
      },
-     'ppc64le': {
-         'rootfs_size': 3
-     },
      '*': {
          'noupgrade': True
+         'rootfs_size': 3
      }
   })
 ]