Merge branch 'cross-fasdump-v2'

- Introduces a portable fasdumper that the compiler can use for
  cross-compiling.

- Adapt the build system to use it.  This form is not final: we
  should really be using GNU configure's build/host/target form.

- Fix up the i386 back end, particularly floating-point stuff.

- Split svm1 into four architectures: svm1-32be, svm1-32le,
  svm1-64be, svm1-64le.  This way you can, e.g., use your x86 laptop
  to cross-build an svm1-32le system to run on an arm32 machine.

- Various minor other fixes for cross-compilation.

diff --cc src/runtime/runtime.pkg
Simple merge

diff --cc tests/check.scm
index 4eb7aa03a47e9eecb74fba9b101be90c697f13bc,a0dd7b452fddb8c121d17105e463674134d14a8f..632a933296fd505157aa5d2fb7dde8ad832dd72b
--- 1/tests/check.scm
--- 2/tests/check.scm
+++ b/tests/check.scm
@@@ -40,9 -40,10 +40,11 @@@ USA
  
  (define known-tests
    '(
+     ("compiler/test-fasdump" (compiler portable-fasdump))
      "compiler/test-fgopt-conect"
+     "compiler/test-toplev"
      "compiler/test-varname"
 +    "compiler/test-y"
      "microcode/test-chacha"
      ;++ Kludge to run the flonum cast tests interpreted and compiled --
      ;++ the compiler has a bug with negative zero.