msm: rpc: hold spinlock while doing wait_event
msm: rpc: hold spinlock while doing wait_event

To prevent a race condition between wake_up called by
msm_rpcrouter_xprt_notify and wait_event in rr_read
hold a spinlock irqsave to prevent the system from going into
sleep when there is pending SMD data to process.

CRs-Fixed: 393416
Change-Id: Ic329c785fa8272857b7f067819d51a516a9cdc0d
Signed-off-by: Angshuman Sarkar <3afe13a0b57cef18da182e020d86b448b1b8187f@codeaurora.org>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas