Fix configure script on FreeBSD
Fix configure script on FreeBSD

* x86-64 architectures are reported as amd64 by uname -r
* FreeBSD platform don't need -ldl for linking

alfonsokim/tinycc,gfwilliams/tinycc,seyko2/tinycc,melkior/tinycc,seyko2/tinycc,leeduhem/tinycc,gfwilliams/tinycc,Saectar/inherpreter,mingodad/tinycc,mingodad/tinycc,run4flat/tinycc,metaeducation/tcc,alfonsokim/tinycc,Archs/TinyCC,mirror/tinycc,andreiw/tinycc,andrewchambers/tccmirror,alfonsokim/tinycc,FriedBreakfast/tcc,melkior/tinycc,fstudio/tinycc,metaeducation/tcc,melkior/tinycc,Archs/TinyCC,rchandramouli/tinycc,andrewchambers/tccmirror,andreiw/tinycc,seyko2/tinycc,leeduhem/tinycc,Saectar/inherpreter,gfwilliams/tinycc,Saectar/inherpreter,FriedBreakfast/tcc,leeduhem/tinycc,melkior/tinycc,Saectar/inherpreter,rchandramouli/tinycc,melkior/tinycc,gfwilliams/tinycc,Archs/TinyCC,mingodad/tinycc,rchandramouli/tinycc,rchandramouli/tinycc,mirror/tinycc,leeduhem/tinycc,leeduhem/tinycc,avih/tinycc,run4flat/tinycc,metaeducation/tcc,avih/tinycc,FriedBreakfast/tcc,Saectar/inherpreter,fstudio/tinycc,fstudio/tinycc,Archs/TinyCC,seyko2/tinycc,andrewchambers/tccmirror,code4game/tinycc,code4game/tinycc,andrewchambers/tccmirror,alfonsokim/tinycc,metaeducation/tcc,FriedBreakfast/tcc,run4flat/tinycc,metaeducation/tcc,avih/tinycc,gfwilliams/tinycc,mingodad/tinycc,fstudio/tinycc,avih/tinycc,andreiw/tinycc,FriedBreakfast/tcc,code4game/tinycc,Archs/TinyCC,andrewchambers/tccmirror,run4flat/tinycc,fstudio/tinycc,run4flat/tinycc,mirror/tinycc,mirror/tinycc,alfonsokim/tinycc,seyko2/tinycc,rchandramouli/tinycc