Remove unused private members

One is not used, the others are not even initialized, so don't use the
memory.

qsoundeffect_pulse_p.h:172:20: warning: private field 'm_resourceStatus' is not used [-Wunused-private-field]
qvideowidget_p.h:211:25: warning: private field 'm_aspectRatioMode' is not used [-Wunused-private-field]
qalsaaudioinput.h:156:22: warning: private field 'timestamp' is not used [-Wunused-private-field]
qalsaaudiooutput.h:135:22: warning: private field 'timestamp' is not used [-Wunused-private-field]

Change-Id: I7c9f50d57c4d29ee0dfd7dc086771d721cdb5b05
Reviewed-by: Yoann Lopes <yoann.lopes@theqtcompany.com>