updating MXNet version to 1.6.0 in base.h for C APIs (#16905)
updating MXNet version to 1.6.0 in base.h for C APIs (#16905)


zhreshold/mxnet,yajiedesign/mxnet,leezu/mxnet,eric-haibin-lin/mxnet,sxjscience/mxnet,yajiedesign/mxnet,leezu/mxnet,apache/incubator-mxnet,eric-haibin-lin/mxnet,larroy/mxnet,ForkedReposBak/mxnet,leezu/mxnet,tlby/mxnet,zhreshold/mxnet,leezu/mxnet,eric-haibin-lin/mxnet,larroy/mxnet,tlby/mxnet,szha/mxnet,DickJC123/mxnet,szha/mxnet,tlby/mxnet,larroy/mxnet,szha/mxnet,DickJC123/mxnet,leezu/mxnet,yajiedesign/mxnet,yajiedesign/mxnet,eric-haibin-lin/mxnet,zhreshold/mxnet,tlby/mxnet,DickJC123/mxnet,larroy/mxnet,eric-haibin-lin/mxnet,larroy/mxnet,sxjscience/mxnet,zhreshold/mxnet,sxjscience/mxnet,tlby/mxnet,sxjscience/mxnet,ForkedReposBak/mxnet,zhreshold/mxnet,larroy/mxnet,eric-haibin-lin/mxnet,tlby/mxnet,yajiedesign/mxnet,tlby/mxnet,apache/incubator-mxnet,ForkedReposBak/mxnet,zhreshold/mxnet,larroy/mxnet,sxjscience/mxnet,sxjscience/mxnet,ForkedReposBak/mxnet,leezu/mxnet,ForkedReposBak/mxnet,DickJC123/mxnet,zhreshold/mxnet,leezu/mxnet,leezu/mxnet,yajiedesign/mxnet,szha/mxnet,yajiedesign/mxnet,ForkedReposBak/mxnet,szha/mxnet,zhreshold/mxnet,leezu/mxnet,yajiedesign/mxnet,eric-haibin-lin/mxnet,sxjscience/mxnet,tlby/mxnet,larroy/mxnet,sxjscience/mxnet,ForkedReposBak/mxnet,apache/incubator-mxnet,szha/mxnet,szha/mxnet,szha/mxnet,ForkedReposBak/mxnet,tlby/mxnet,eric-haibin-lin/mxnet,zhreshold/mxnet,sxjscience/mxnet,eric-haibin-lin/mxnet,szha/mxnet,tlby/mxnet,ForkedReposBak/mxnet,yajiedesign/mxnet,apache/incubator-mxnet,larroy/mxnet