soc: qcom: qmi: Fix possible use after free

Packets in transmit path maybe freed before checking for the
content for bearer level flow control limit.
Fix this by checking this before the transmit.

CRs-Fixed: 2259239
Change-Id: If50af5a2e6c6bb3bfddfe583c422c7f648783aea
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>