libc: generate syscall stubs in one big file...

...all the better to switch to a genrule rather than checking in
generated source.

This also removes all the code in the script to deal with git,
rather than fix it. We won't need that where we're going.

Test: boots
Change-Id: I468ce019d4232a7ef27e5cb5cfd89f4c2fe4ecbd
diff --git a/libc/Android.bp b/libc/Android.bp
index 23ccbe3..ce9b396 100644
--- a/libc/Android.bp
+++ b/libc/Android.bp
@@ -1246,22 +1246,22 @@
     srcs: ["bionic/__set_errno.cpp"],
     arch: {
         arm: {
-            srcs: ["arch-arm/syscalls/**/*.S"],
+            srcs: ["arch-arm/syscalls.S"],
         },
         arm64: {
-            srcs: ["arch-arm64/syscalls/**/*.S"],
+            srcs: ["arch-arm64/syscalls.S"],
         },
         mips: {
-            srcs: ["arch-mips/syscalls/**/*.S"],
+            srcs: ["arch-mips/syscalls.S"],
         },
         mips64: {
-            srcs: ["arch-mips64/syscalls/**/*.S"],
+            srcs: ["arch-mips64/syscalls.S"],
         },
         x86: {
-            srcs: ["arch-x86/syscalls/**/*.S"],
+            srcs: ["arch-x86/syscalls.S"],
         },
         x86_64: {
-            srcs: ["arch-x86_64/syscalls/**/*.S"],
+            srcs: ["arch-x86_64/syscalls.S"],
         },
     },
     name: "libc_syscalls",
@@ -2455,19 +2455,19 @@
 
     arch: {
         arm: {
-            srcs: ["arch-arm/syscalls/__rt_sigprocmask.S"],
+            srcs: ["arch-arm/syscalls.S"],
         },
         arm64: {
-            srcs: ["arch-arm64/syscalls/__rt_sigprocmask.S"],
+            srcs: ["arch-arm64/syscalls.S"],
         },
         x86: {
             srcs: [
                 "arch-x86/bionic/__libc_init_sysinfo.cpp",
-                "arch-x86/syscalls/__rt_sigprocmask.S",
+                "arch-x86/syscalls.S",
             ],
         },
         x86_64: {
-            srcs: ["arch-x86_64/syscalls/__rt_sigprocmask.S"],
+            srcs: ["arch-x86_64/syscalls.S"],
         },
     },