ARM: dts: msm: Add BLSP2 UART1 definitions for APQ8084

Add the device tree entry, clock table entries, and gpiomux
table entries needed to support the BLSP2 UART1 device on
the APQ8084 target.

Change-Id: I3035a7c849ebb320a42cdfee6c0701a2fc95e6e8
Signed-off-by: Stepan Moskovchenko <stepanm@codeaurora.org>