qcacmn: handle integer underflow in util_gen_new_ie

Handle integer underflow for subie_len in util_gen_new_ie

Bug: 318386769
Test: Regression Test
Change-Id: I2f73e5a7e0462100deae1e85e6a51f77bfc46b95
CRs-Fixed: 3582487
Signed-off-by: Hsiu-Chang Chen <hsiuchangchen@google.com>
1 file changed