RFR(M): 8160245: C1: Clean up platform #defines in c1_LIR.hpp.

[Lindenmaier, Goetz]

Sorry, the webrev URL was missing, added below:

Hi,

c1_LIR.hpp defines a row of functions guarded by platform 
defines. This is bad style and hinders new platform ports. 
(I'm working on S390 aka Z :))

This change removes the majority of these defines. It introduces 
common headers, and moves implementations to c1_LIR_<cpu>.cpp files. 

It guards single_softfp() and double_softfp() by __SOFTFP__. 
This is not used in any openJdk platform. I can not test this 
on the closed platforms ARM32 and PPC32. 

It removes the guard around the LIR_Address constructor. There 
is no point in guarding this code, verify() assures by 
assertions that it can not be misused. I also introduce a new 
constructor that leaves out the scale argument and introduced
some usages on X86.

This change also moves verify() to the new platform files. In the 
header, LIR_ADDRESS_PD_VERIFY was used to guard usage 
of pd_verify(). Neither of these are used in openJdk. If this define 
is used in the closed ports pd_verify() must be renamed to verify(). 

The code that was previously guarded by ARM, ARM32 or PPC32 is 
moved to a properly guarded section in c1_LIR.cpp. Actually, 
it should be moved to according new files c1_LIR_<cpu>.cpp in 
the closed ports. But this way the change should basically 
work for the closed ports.

I added fnoreg on x86 to note down the code similarly on all
Platforms. 

I cleaned up a flag with a limited range on PPC_32.

Please review this change. I please need a sponsor.
https://bugs.openjdk.java.net/browse/JDK-8160245
http://cr.openjdk.java.net/~goetz/wr16/8160245-simplifyC1/webrev.01/

I built and tested this on linuxx86_64, solaris_sparc and the ppc platforms.

Best regards,
  Goetz