AIX: cppgc: Add .csect directive to inline asm

Port 3c809e0d

Original Commit Message:

    .type directive is required on arm to enable ARM/Thumb interworking.

R=mlippautz@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: I5aa258033fc89dbb1165b926c3351abc45ed9d85
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2154836Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#67214}

src/heap/cppgc/asm/ppc/push_registers_asm.cc

@@ -19,6 +19,7 @@
 asm(
 #if defined(_AIX)
     ".globl .PushAllRegistersAndIterateStack, hidden    \n"
+    ".csect .text[PR]                                   \n"
     ".PushAllRegistersAndIterateStack:                  \n"
 #else
     ".globl PushAllRegistersAndIterateStack             \n"