Merge ~andreserl/maas:lp1740925_fix_centos_efi_2.3 into maas:2.3

[Andres Rodriguez]

LP: #1740925 - Correctly set the bootloader for centos on EFI localboot

Backport f789b68 from master

[Andres Rodriguez (andreserl)]

selfie!

review: Approve

diff --git a/src/provisioningserver/templates/uefi/config.local.amd64.template b/src/provisioningserver/templates/uefi/config.local.amd64.template
index 42e39eb..438cb8c 100644
--- a/src/provisioningserver/templates/uefi/config.local.amd64.template
+++ b/src/provisioningserver/templates/uefi/config.local.amd64.template
@@ -6,6 +6,12 @@ menuentry 'Local' {
     {{if kernel_params.osystem == "windows"}}
     search --set=root --file /efi/Microsoft/Boot/bootmgfw.efi
     chainloader /efi/Microsoft/Boot/bootmgfw.efi
+    {{elif kernel_params.osystem == "centos"}}
+    search --set=root --file /efi/centos/grubx64.efi
+    chainloader /efi/centos/grubx64.efi
+    {{elif kernel_params.osystem == "rhel"}}
+    search --set=root --file /efi/redhat/grubx64.efi
+    chainloader /efi/redhat/grubx64.efi
     {{else}}
     search --set=root --file /efi/ubuntu/grubx64.efi
     chainloader /efi/ubuntu/grubx64.efi