add fetch kernel for CPU

 add fetch kernel for FPGA, GPU_MALI

# Conflicts:
#	src/operators/kernel/fpga/feed-kernel.cpp

update conv kernel

add fetch kernel for CPU

fix depthwise_conv_kernel of opencl

 fix image memory copy bug

Opencl

fix compilation problem

update fetch_kernel with CLTensor

 update conv kernel cl

fix relu cl_image

add PADDLE_MOBILE_CL macro in fetch_op.h

 update cl tensor

Opencl