/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/ is in linux-gcp-headers-4.18.0-1005 4.18.0-1005.6~18.04.1.
This file is owned by root:root, with mode 0o755.
..
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/arc
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/arm
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/arm64
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/c6x
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/dt-bindings
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/h8300
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/microblaze
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/mips
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/nios2
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/openrisc
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/powerpc
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/sh
/usr/src/linux-gcp-headers-4.18.0-1005/scripts/dtc/include-prefixes/xtensa