Doesn't compile without W3_IC4 defined

[anton-seaice]

Describe the bug
When the W3_IC4_NUMERICS macro definition was added, this prevents building when not wanting to build with W3_IC4.

At these lines :

WW3/model/src/w3srcemd.F90

Lines 2091 to 2093 in 1c11fc1

	#ifndef W3_IC4_NUMERICS
	CALL W3SIC4 ( SPEC,DEPTH, CG1, IX, IY, VSIC, VDIC )
	#endif

when neither W3_IC4 nor W3_IC4_NUMERICS are defined, it tries to call W3SIC4, which is incorrect, as W3_IC4 is not defined. It should only call W3SIC4 when WC_IC4 is defined and W3_IC4_NUMERICS is not defined.

There is the same issue at this line

WW3/model/src/w3srcemd.F90

Lines 2122 to 2124 in 1c11fc1

	#ifndef W3_IC4_NUMERICS
	ATT=EXP(ICE*VDIC(IS)*DTG)
	#endif

To Reproduce
Build without W3_IC4 set

Expected behavior
Should build & allow for attenuation schemes other than IC4

Screenshots

Additional context
Ill raise a PR, I have written this very poorly!

ping @dabail10