iommu-api: Check iommu_found before using IOMMU ops

Check that a set of IOMMU ops has been registered before
using them, as this may result in dereferencing a NULL
pointer.

Change-Id: I11f81a236c9bfd2e1a1899c7fee1f43125fdb004
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>
1 file changed