[Ada] Disable expansion of 'Min/'Max of floating point types

[Ada] Disable expansion of 'Min/'Max of floating point types

2019-07-01  Javier Miranda  <miranda@adacore.com>

gcc/ada/

	* exp_attr.adb (Expand_Min_Max_Attribute): Disable expansion of
	'Min/'Max on integer, enumeration, fixed point and floating
	point types since the CCG backend now provides in file
	standard.h routines to support it.

From-SVN: r272858