clk: txl: fix gpu clock can not be changed [1/1]

clk: txl: fix gpu clock can not be changed [1/1]

PD#SWPL-2909

Problem:
The gpu clock rate can not be changed.

Solution:
1.it called meson_init_gpu function which used by txlx
  in txl clock driver, change it to meson_txl_gpu_init function.
2.the /sys/kernel/debug/aml_clk/clk_test node can not work
  in txl platform, Initial value for clk_numbers which needed
  by clk_test driver.

Verify:
test passed on P321

Change-Id: Iade63691edf5b39325f34abb4789d48d33339329
Signed-off-by: Jian Hu <jian.hu@amlogic.com>