shared: Add get_be32()
shared: Add get_be32()

Add helper to avoid possible unaligned memory access when handling
uint32 value using big-endian representation.

pkarasev3/bluez,mapfau/bluez,pkarasev3/bluez,pkarasev3/bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,mapfau/bluez,ComputeCycles/bluez,mapfau/bluez,pkarasev3/bluez,silent-snowman/bluez,pstglia/external-bluetooth-bluez,pstglia/external-bluetooth-bluez,pstglia/external-bluetooth-bluez,silent-snowman/bluez,silent-snowman/bluez,ComputeCycles/bluez,ComputeCycles/bluez,mapfau/bluez,ComputeCycles/bluez