Merge pull request #7781 from kaspar030/remove_coreif_ng

core/include/arch/irq_arch.h

core/include/arch/panic_arch.h

core/include/arch/thread_arch.h

core/include/irq.h

core/include/panic.h

core/include/thread.h

core/panic.c

cpu/atmega1281/Makefile.include

cpu/atmega2560/Makefile.include

cpu/atmega328p/Makefile.include

cpu/atmega_common/irq_arch.c

cpu/atmega_common/thread_arch.c

cpu/cortexm_common/irq_arch.c

cpu/cortexm_common/thread_arch.c

cpu/lm4f120/cpu.c

cpu/mips32r2_common/cpu.c

cpu/mips32r2_common/irq_arch.c

cpu/mips32r2_common/periph/timer.c

cpu/mips32r2_common/thread_arch.c

cpu/msp430_common/cpu.c