ELF2 main programs pass src/testsuite and upx-testsuite-v2

Decompressing lzma required many adjustments.
Backwards compatibility probably is broken for
    stub/amd64-win64.pe.h
    stub/arm64-win64.pe.h
Also: shared libraries need memfd_create.
	modified:   ../misc/testsuite/upx_testsuite_1-expected_sha256sums.sh
	modified:   p_lx_elf.cpp
	modified:   stub/Makefile
	modified:   stub/scripts/xstrip.py
	modified:   stub/src/amd64-expand.S
	modified:   stub/src/arch/amd64/lzma_d.S
	modified:   stub/src/arch/arm/v4a/lzma_d.S
	modified:   stub/src/arch/arm/v4t/macros.S
	modified:   stub/src/arch/arm64/v8/lzma_d.S
	modified:   stub/src/arch/powerpc/32/lzma_d.S
	modified:   stub/src/arch/powerpc/64le/lzma_d-common.S
	modified:   stub/src/arm.v4a-expand.S
	modified:   stub/src/arm.v4t-linux.shlib-init.S
	modified:   stub/src/arm64-expand.S
	modified:   stub/src/i386-expand.S
	modified:   stub/src/mips.r3000-expand.S
	modified:   stub/src/powerpc-expand.S
	modified:   stub/src/powerpc-linux.elf-entry.S
	modified:   stub/src/powerpc-linux.elf-fold.S
	modified:   stub/src/powerpc64-expand.S
	modified:   stub/src/powerpc64-linux.elf-entry.S
	modified:   stub/src/powerpc64-linux.elf-fold.S
           plus generated *.h *.map *.dump

src/stub/tmp/amd64-darwin.dylib-entry.bin.dump

@@ -17,7 +17,6 @@ Idx Name          Size      VMA               LMA               File off  Algn
 SYMBOL TABLE:
 0000000000000000 l    d  NRV_HEAD 0 NRV_HEAD
 0000000000000000 l    d  LZMA_DEC30 0 LZMA_DEC30
-0000000000000000 l    d  MACHMAINY 0 MACHMAINY
 0000000000000000 l    d  MACHMAINZ 0 MACHMAINZ
 0000000000000000 l    d  MACHMAINX 0 MACHMAINX
 0000000000000000 l    d  NRV2E 0 NRV2E
@@ -27,10 +26,12 @@ SYMBOL TABLE:
 0000000000000000 l    d  LZMA_DEC10 0 LZMA_DEC10
 0000000000000000 l    d  LZMA_DEC20 0 LZMA_DEC20
 0000000000000000 l    d  NRV_TAIL 0 NRV_TAIL
+0000000000000000 l    d  MACHMAINY 0 MACHMAINY
 0000000000000000 g       MACHMAINX 0 _start
 0000000000000000         *UND* 0 eof_n2e
 0000000000000000         *UND* 0 eof_n2d
 0000000000000000         *UND* 0 eof_n2b
+0000000000000000         *UND* 0 eof_lzma
 0000000000000011 g       MACHMAINY 0 end_decompress
 
 RELOCATION RECORDS FOR [MACHMAINX]:
@@ -58,7 +59,7 @@ OFFSET           TYPE              VALUE
 
 RELOCATION RECORDS FOR [LZMA_DEC30]:
 OFFSET           TYPE              VALUE
-0000000000000015 R_X86_64_PC32     MACHMAINY+0xfffffffffffffffc
+0000000000000015 R_X86_64_PC32     eof_lzma+0xfffffffffffffffc
 
 RELOCATION RECORDS FOR [MACHMAINZ]:
 OFFSET           TYPE              VALUE