Number of dynamically mapped interrupts for IPU

configname: CONFIG_MX3_IPU_IRQS

Linux Kernel Configuration
└─>Device Drivers
└─>DMA Engine support
└─>Number of dynamically mapped interrupts for IPU
In linux kernel since version 2.6.29 (release Date: 2009-03-23)  
Out of 137 interrupt sources on i.MX31 IPU only very few are used.
To avoid bloating the irq_desc[] array we allocate a sufficient
number of IRQ slots and map them dynamically to specific sources.