There was a bug where sdb_find_by_identity would be exported by
glue/cplusplus.cpp, but the type might not match the header,
depending on the value of EB_STATUS_OR_VOID_T.

Fixing this requires making the method inline. However, that removes
the symbol from the library, which is a breaking change to the ABI
for C++. The API remains compatible, however.

As we do not remap nested addresses, using msi_base=0 is harmless.

format/slave.c: In function 'eb_device_slave':
format/slave.c:165:7: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]
       tag = be32toh(*(uint32_t*)&buffer[4]);

transport/dev.c: In function 'eb_dev_send':
transport/dev.c:185:3: warning: ignoring return value of 'write', declared with attribute warn_unused_result [-Wunused-result]
   write(link->fdes, buf, len);