misc: tegra-profiler: fix crash in power_clk stop

misc: tegra-profiler: fix crash in power_clk stop

Fix crash in profiler when using gpu and emc clocks: using
the freed clock source can cause the kernel panic.
Remove redundant clk_get_sys calls.

Bug 1918185

Change-Id: I421049c7a30fad6356f7300226e84794cecf0673
Signed-off-by: Igor Nabirushkin <inabirushkin@nvidia.com>
Reviewed-on: http://git-master/r/1476299
(cherry picked from commit 8b0d7e1748b31dd87ab2837a6b9f0a1d2e3d6ecc)
Reviewed-on: http://git-master/r/1482967
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: svccoveritychecker <svccoveritychecker@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Dmitry Antipov <dantipov@nvidia.com>
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>