Some others have also reported that LR 5's map module is disabled in China:
According to the articles below, China requires online mapping services to be licensed by the government, and licenses are only granted to companies that have no more than 50% foreign ownership and that store the mapping data on servers in China. So foreign companies like Google have to obtain licenses via partnerships with Chinese companies. Perhaps Adobe (or China) has determined that the LR map module needs its own license (separate from any Google license):
Or it may be simply that Google Maps is currently blocked in much of China:
You might repost your query on Adobe's official feedback site, Recently active topics in Photoshop Family about Photoshop Lightroom. Adobe employees frequent that site much more frequently than this user-to-user forum.