Naming rules in MKLDNN related codes

[luotao1]

Paddle use CamelCase naming convention. For example, all the functions of pool_op.cc use CamelCase naming convention, but pool_mkldnn_op.cc use gethash, not GetHash. Could you please go over all the MKLDNN related codes in fluid version, and correct it? @jczaja @kbinias @mozga-intel @pzelazko-intel @tpatejko

[mozga-intel]

@luotao1 Thank you for your issue. If the mkldnn layout will be ready to merge, the changes will be visible in these PR.

• MKLDNN layout: Support for sum operator MKLDNN layout: Support for sum operator #11102
• MKLDNN layout: Support for pool operator MKLDNN layout: Support for pool operator #11101
• MKLDNN layout: Support for convolution operator MKLDNN layout: Support for convolution operator #11099
• MKLDNN layout: Support for batch norm operator MKLDNN layout: Support for batch norm operator #11098
• MKLDNN layout: Support for activation operator MKLDNN layout: Support for activation operator #11124

[luotao1]

@mozga-intel I see it, thanks very much!