Hi,

The ref 3360b7d9ff85172dc3d2275c35caec71149b35ef breaks building packages that inherit from dpkg-raw and use DEBIAN_BUILD_DEPENDS like the minimal reproducer below.
During do_install_builddeps, the mount points are not mounted (or get unmounted).
Also latest next (591a537d3cc9f3ef35e008fdff0fe631714aa68d) is affected.

inherit dpkg-raw
DESCRIPTION = "Reproduce ISAR mount issues"
DEBIAN_BUILD_DEPENDS = "htop"

Build error:
Err:4 file:/isar-apt isar/main amd64 Packages
  File not found - /isar-apt/dists/isar/main/binary-amd64/Packages (2: No such file or directory)
Get:5 file:/isar-apt isar/main Translation-en
Ign:5 file:/isar-apt isar/main Translation-en
Reading package lists...
E: Failed to fetch file:/isar-apt/dists/isar/main/binary-amd64/Packages  File not found - /isar-apt/dists/isar/main/binary-amd64/Packages (2: No such file or directory)

Best regards,
Felix