staging: rtl8723bs: remove assignment in condition in os_dep/ioctl_linux.c

staging: rtl8723bs: remove assignment in condition in os_dep/ioctl_linux.c

fix the following checkpatch warning:

ERROR: do not use assignment in if condition
2607: FILE: drivers/staging/rtl8723bs/os_dep/ioctl_linux.c:2607:
+	if (0 != (ret = rtw_change_ifname(padapter, new_ifname)))
--
ERROR: do not use assignment in if condition
4239: FILE: drivers/staging/rtl8723bs/os_dep/ioctl_linux.c:4239:
+	if (!(ext = vmalloc(len)))
--
ERROR: do not use assignment in if condition
4253: FILE: drivers/staging/rtl8723bs/os_dep/ioctl_linux.c:4253:
+	if (!(ext_dbg = vmalloc(len))) {

Signed-off-by: Fabio Aiuto <fabioaiuto83@gmail.com>
Link: https://lore.kernel.org/r/98b58790ae7c791d091b301bccf67a70c41ec599.1616600897.git.fabioaiuto83@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>