cmsis: patch fpu in asm for armcc5

For FPU, use armasm to select fpu selection. This will be fixed upstream in the next version of CMSIS. Meanwhile, we use our local patch.

Taken from --cpu selection for armasm:

--cpu           | {FPU}
Cortex-M4.fp.sp | VFPv4_SP_D16
Cortex-M7.fp.sp | FPv5-SP
Cortex-M7.fp.dp | FPv5_D16

Tracking issue: ARM-software/CMSIS_5#1266

cmsis/CMSIS_5/CMSIS/RTOS2/RTX/Source/TOOLCHAIN_ARM/TARGET_RTOS_M4_M7/irq_cm4f.S

@@ -28,7 +28,7 @@
 RTX_STACK_CHECK EQU      0
 #endif
 
-                IF       ({FPU}="FPv4-SP")
+                IF       ({FPU}="FPv4-SP") || ({FPU}="VFPv4_SP_D16") || ({FPU}="FPv5-SP") || ({FPU}="FPv5_D16")
 FPU_USED        EQU      1
                 ELSE
 FPU_USED        EQU      0