deps: V8: cherry-pick 7b91e3e2cbaf

Original commit message:

    s390: use %r15 instead of %sp

    Some compilers do not recognize %sp and output:
    ```
    error: invalid register
    ```

    Change-Id: I2e1b64dd0e799a03afccbd12f5b2db17b3130e07
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/6603554
    Reviewed-by: Michael Lippautz <[email protected]>
    Commit-Queue: Milad Farazmand <[email protected]>
    Reviewed-by: Junliang Yan <[email protected]>
    Cr-Commit-Position: refs/heads/main@{#100576}

Refs: v8/v8@7b91e3e
PR-URL: #59485
Refs: nodejs/build#4091
Reviewed-By: Michaël Zasso <[email protected]>
Reviewed-By: Joyee Cheung <[email protected]>
Reviewed-By: Luigi Pinca <[email protected]>
Reviewed-By: Juan José Arboleda <[email protected]>
Reviewed-By: Rafael Gonzaga <[email protected]>

Author: Milad Fa

common.gypi

@@ -38,7 +38,7 @@
 
     # Reset this number to 0 on major V8 upgrades.
     # Increment by one for each non-official patch applied to deps/v8.
-    'v8_embedder_string': '-node.19',
+    'v8_embedder_string': '-node.20',
 
     ##### V8 defaults for Node.js #####
 

deps/v8/src/heap/base/asm/s390/push_registers_asm.cc

@@ -21,17 +21,17 @@ asm(".text                                              \n"
     "PushAllRegistersAndIterateStack:                   \n"
     // Push all callee-saved registers.
     // r6-r13, r14 and sp(r15)
-    "  stmg %r6, %sp, 48(%sp)                           \n"
+    "  stmg %r6, %r15, 48(%r15)                         \n"
     // Allocate frame.
-    "  lay %sp, -160(%sp)                               \n"
+    "  lay %r15, -160(%r15)                             \n"
     // Pass 1st parameter (r2) unchanged (Stack*).
     // Pass 2nd parameter (r3) unchanged (StackVisitor*).
     // Save 3rd parameter (r4; IterateStackCallback).
     "  lgr %r5, %r4                                     \n"
     // Pass sp as 3rd parameter. 160+48 to point
     // to callee saved region stored above.
-    "  lay %r4, 208(%sp)                                \n"
+    "  lay %r4, 208(%r15)                               \n"
     // Call the callback.
     "  basr %r14, %r5                                   \n"
-    "  lmg %r14,%sp, 272(%sp)                           \n"
+    "  lmg %r14,%r15, 272(%r15)                         \n"
     "  br %r14                                          \n");