build: Redo LLVM macros to disable JIT rather than stop build if headers not found. * configure.ac: Move functionality for OCTAVE_LLVM_IR_DIR, OCTAVE_LLVM_IRBUILDER_HEADER, OCTAVE_LLVM_DATALAYOUT_HEADER macros from acinclude.m4 to configure.ac. * m4/acinclude.m4: Delete OCTAVE_LLVM_IR_DIR, OCTAVE_LLVM_IRBUILDER_HEADER, OCTAVE_LLVM_DATALAYOUT_HEADER macros. Eliminate unnecessary else clause of OCTAVE_LLVM_FUNCTION_ADDATTRIBUTE_API, OCTAVE_LLVM_FUNCTION_ADDFNATTR_API, OTAVE_LLVM_CALLINST_ADDATTRIBUTE_API macros.

clear;

disp('1st problem');
s=-1;
c=[10,6,4]';
a=[1,1,1;...
   10,4,5;...
   2,2,6];
b=[100,600,300]';
ctype=['U','U','U']';
lb=[0,0,0]';
ub=[]';
vartype=['C','C','C']';
param.msglev=3;
param.lpsolver=1;
param.save=1;
[xmin,fmin,status,extra]=glpk(c,a,b,lb,ub,ctype,vartype,s,param)
lpsolver = param.lpsolver;
save_pb = param.save;
[xmin,fmin,status,extra]=glpkmex(s,c,a,b,ctype,lb,ub,vartype,param,lpsolver,save_pb)