modprobe-small: if concurrent module load did not succeed, wait

usecase:
two sd cards are being mounted in parallel at same time on dual core. example
modules which are getting loaded is  nls_cp437. While one module is being
loaded , it makes state in /proc/modules as 'coming' and then starts doing its
module init function (in our case - registering nls). meanwhile on other core,
if modprobe returns that is has already been loaded, then it will continue
and search for the nls list which is not yet finished from first module init.
This fails resulting in not mounting sd card.

function                                             old     new   delta
process_module                                       667     746     +79

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
1 file changed