topology: Allow a data section to contain multiple tuples objects

It's easy to use a vendor tuples object to define a C structure instance as
vendor specific parameter for kernel drivers. And sometimes the kernel drivers
may want a group of structures. So this patch will allow user to define multiple
vendor tuples objects in a data section, to avoid defining multiple data
sections and each data section only has 1 vendor tuples object.

There is no ABI change in this patch.

Signed-off-by: Mengdong Lin <mengdong.lin@linux.intel.com>
Signed-off-by: Fuwei Tang <fuweix.tang@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>