Fix ARM fegetexceptflag.c

The ARM fegetexceptflag() implementation was accidentally replaced with
fesetexceptflag() during refactoring in b7a6e02.
Restore the original implementation.

Tested on Cortex-M7.

Author: matthew-reynolds

newlib/libm/machine/arm/fegetexceptflag.c

@@ -37,9 +37,7 @@ int fegetexceptflag(fexcept_t *flagp, int excepts)
 	fexcept_t __fpsr;
 
 	vmrs_fpscr(__fpsr);
-	__fpsr &= ~excepts;
-	__fpsr |= *flagp & excepts;
-	vmsr_fpscr(__fpsr);
+	*flagp = __fpsr & excepts;
 #endif
 	return (0);
 }