staging: rtl8188eu: remove redundant initialization of 'pwrcfgcmd'

Structure pwrcfgcmd is being zero'd at initialization however this
value is never read as few statements later in a loop it is being
assigned a new value, hence the initialization is redundant and
can be removed.

Cleans up clang warning:
drivers/staging/rtl8188eu/hal/pwrseqcmd.c:25:20: warning: Value stored
to 'pwrcfgcmd' during its initialization is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>