ARM: dts: lpc32xx: reparent SIC1 and SIC2 interrupts from MIC

The change adds separate device nodes for SIC1 and SIC2 interrupt
controllers and reparents all defined SIC1 and SIC2 interrupt
producers to the correspondent interrupt controller, this is needed to
perform switching to a new LPC32xx MIC/SIC interrupt controller driver.

Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>