bug#45826: SBCL / Common Lisp packages fail to build on aarch64

[Leo Famulari]

I noticed that many Common Lisp or SBCL-related packages are failing to
build on the aarc64 platform on our build farm, due the failure to build
SBCL:

>From the log of <https://ci.guix.gnu.org/build/180326/details>:

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//entering make-target-2.sh
//doing warm init - compilation phase
This is SBCL 2.1.0, an implementation of ANSI Common Lisp.
More information about SBCL is available at <http://www.sbcl.org/>.

SBCL is free software, provided as is, with absolutely no warranty.
It is mostly in the public domain; some portions are provided under
BSD-style licenses.  See the CREDITS and COPYING files in the
distribution for more information.
Initial page table:
Gen  Boxed   Code    Raw  LgBox LgCode  LgRaw  Pin       Alloc     Waste        
Trig      WP GCs Mem-age
 6     397    250      0      0      0      0    0    42335440     66352     
2000000     647   0  0.0000
           Total bytes allocated    =      42335440
           Dynamic-space-size bytes =    3221225472
COLD-INIT... (Length(TLFs)= 9736)
Disassembler: 72 printers, 0 prefilters, 4 labelers
CORRUPTION WARNING in SBCL pid 1774 tid 1774:
Memory fault at 0xfffffffffffffffa (pc=0x1002199f70)
The integrity of this image is possibly compromised.
Exiting.
Error opening /dev/tty: No such device or address
Welcome to LDB, a low-level debugger for the Lisp runtime environment.
ldb> 
real    0m6.120s
user    0m5.958s
sys     0m0.137s
command "sh" "make.sh" "clisp" 
"--prefix=/gnu/store/j1ciw4dc8iskd5fdcw0s1ba08kkg7vx6-sbcl-2.1.0" 
"--dynamic-space-size=3072" "--with-sb-core-compression" 
"--with-sb-xref-for-internals" failed with status 1
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It appears that SBCL can support this platform. However, until we make
it work, I plan to remove aarch64 from the "supported-systems" of sbcl,
to avoid attempting these builds.