lpbin: Fix thumbnail extraction bug
lpbin: Fix thumbnail extraction bug

It should not do g_free() for the return value of
gst_element_factory_get_klass function
So, I remove unnecessary exception handling and g_free code

:issues addressed:
[GF-42534] Videos not presented with thumbnails

Change-Id: I2424534d8818b87bdb8711c7020f29e6bb5e7c52
Reviewed-on: https://gpro.palm.com/14126
Tested-by: Wonchul Lee <9841bdbec9dbb2acc2dcaaa1dab0491399f0e464@lge.com>
Reviewed-by: HoonHee Lee <41497318ef67053f37c2ac0e974a3369f66d66ec@lge.com>
Reviewed-by: Hyunrae Cho <6668225b847393c9de573d15db4aa1e9c1a5986e@lge.com>
Reviewed-by: WonHo Chun <0776ca6adb6a1e1d566ae6677b1353099e2d7f0f@lge.com>

justinjoy/gst-plugins-lp,justinjoy/gst-plugins-lp