generator.yml: Add PowerPC allmodconfig build for mainline with LLVM 15+

Now that my series to allow big endian ELFv2 to be selected with ld.lld
has been merged into mainline, we can start testing powerpc64
allmodconfig like -next, mirroring commit e4abcea ("generator: Add
PowerPC allmodconfig build").

This adds 25 builds per week:

diff --git a/tmp/estimate-builds.txt b/tmp/.psub.JyBf7GilsO
index 017dbea..b21671c 100644
--- a/tmp/estimate-builds.txt
+++ b/tmp/.psub.JyBf7GilsO
@@ -1,11 +1,11 @@
-Total builds per week: 8232
+Total builds per week: 8257

   - tree: mainline
-    total: 2925
+    total: 2950
     breakdown:
-    - clang-17: 640
-    - clang-16: 640
-    - clang-15: 300
+    - clang-17: 650
+    - clang-16: 650
+    - clang-15: 305
     - clang-14: 280
     - clang-13: 280
     - clang-12: 265

Signed-off-by: Nathan Chancellor <nathan@kernel.org>

generator.yml

@@ -396,6 +396,7 @@ builds:
   - {<< : *ppc64le,           << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_tot}
   - {<< : *ppc64le_fedora,    << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_tot}
   - {<< : *ppc64le_suse,      << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_tot}
+  - {<< : *ppc64_allmod,      << : *mainline,         << : *llvm_full,       boot: false, << : *llvm_tot}
   - {<< : *riscv,             << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_tot}
   - {<< : *riscv_allmod,      << : *mainline,         << : *llvm_full,       boot: false, << : *llvm_tot}
   - {<< : *riscv_alpine,      << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_tot}
@@ -864,6 +865,7 @@ builds:
   - {<< : *ppc64le,           << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_latest}
   - {<< : *ppc64le_fedora,    << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_latest}
   - {<< : *ppc64le_suse,      << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_latest}
+  - {<< : *ppc64_allmod,      << : *mainline,         << : *llvm_full,       boot: false, << : *llvm_latest}
   - {<< : *riscv,             << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_latest}
   - {<< : *riscv_allmod,      << : *mainline,         << : *llvm_full,       boot: false, << : *llvm_latest}
   - {<< : *riscv_alpine,      << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_latest}
@@ -1330,6 +1332,7 @@ builds:
   - {<< : *ppc64le,           << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_15}
   - {<< : *ppc64le_fedora,    << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_15}
   - {<< : *ppc64le_suse,      << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_15}
+  - {<< : *ppc64_allmod,      << : *mainline,         << : *llvm_full,       boot: false, << : *llvm_15}
   - {<< : *riscv,             << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_15}
   - {<< : *riscv_allmod,      << : *mainline,         << : *llvm_full,       boot: false, << : *llvm_15}
   - {<< : *riscv_alpine,      << : *mainline,         << : *llvm_full,       boot: true,  << : *llvm_15}