soc: renesas: rz: Update Renesas RZ/V2N, RZ/V2L according to RZ/V2H

Porting gp_renesas_isr_context variable used in FSP interrupt source
to unify with RZ/V2H and prevent build error since they share the same
hal_renesas source code.

Signed-off-by: Tien Nguyen <tien.nguyen.zg@renesas.com>