make-mod-scripts: pass CROSS_COMPILE to configure and build

Fixes:
|   CALL    /OE/poky-master/build/tmp/work-shared/qemuarm64/kernel-source/scripts/checksyscalls.sh
|   CALL    /OE/poky-master/build/tmp/work-shared/qemuarm64/kernel-source/scripts/atomic/check-atomics.sh
|   LDS     arch/arm64/kernel/vdso/vdso.lds
|   CC      arch/arm64/kernel/vdso/vgettimeofday.o
|   AS      arch/arm64/kernel/vdso/note.o
|   AS      arch/arm64/kernel/vdso/sigreturn.o
|   LD      arch/arm64/kernel/vdso/vdso.so.dbg
|   VDSOSYM include/generated/vdso-offsets.h
|   OBJCOPY arch/arm64/kernel/vdso/vdso.so
| objcopy: Unable to recognise the format of the input file `arch/arm64/kernel/vdso/vdso.so.dbg'
| /OE/poky-master/build/tmp/work-shared/qemuarm64/kernel-source/arch/arm64/kernel/vdso/Makefile:61: recipe for target 'arch/arm64/kernel/vdso/vdso.so' failed

Cc: Bruce Ashfield <bruce.ashfield@gmail.com>
Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Denys Dmytriyenko <denis@denix.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>