tests: drivers: watchdog wwdg of the stm32h573 is erasing sram

When a reset coccurs the sram1 where the m_state value is stored
is erased. Then the board indefinitely reboots.
Avoid this excluding the target board.
Or set the SRAM13_RST bit in the option byte in FLASH_OPTSR2_CUR.

Signed-off-by: Francois Ramu <francois.ramu@st.com>