mesh: use explicit uint32_t when bit shifting left

mesh: use explicit uint32_t when bit shifting left

This addresses a situation when a boolean type is represented by
an integer and performing a left shift on a boolean causes
an integer overflow.

This fixes the following runtime error:
"left shift of 1 by 31 places cannot be represented in type 'int'"

Signed-off-by: Manika Shrivastava <manika.sh@samsung.com>
Signed-off-by: Ayush Garg <ayush.garg@samsung.com>