Add synchronize support in host code

[bauom]

Describe the feature

Adding the ability to use synchronize from the host code.
The call should similar to numba syntax: numba.cuda.synchronize()
The generated code should call: cudaDeviceSynchronize

Test Code

from pyccel import cuda
from pyccel.decorators import kernel

@kernel
def kfunc():
   print("Hello from GPU")

if "__main__" == __name__:
   kfunc[1, 1]()
   cuda.synchronize()