[libc] Enable double math functions on the GPU (#154857)

This patch adds the `acos` math function to the NVPTX build. It also
adds the `sincos` math function to the `math.h` header.

libc/config/gpu/nvptx/entrypoints.txt

@@ -280,6 +280,7 @@ set(TARGET_LIBC_ENTRYPOINTS
 
 set(TARGET_LIBM_ENTRYPOINTS
     # math.h entrypoints
+    libc.src.math.acos
     libc.src.math.acosf
     libc.src.math.acoshf
     libc.src.math.asin

libc/include/math.yaml

@@ -2432,14 +2432,6 @@ functions:
     return_type: double
     arguments:
       - type: double
-  - name: sincosf
-    standards:
-      - gnu
-    return_type: void
-    arguments:
-      - type: float
-      - type: float *
-      - type: float *
   - name: sinf
     standards:
       - stdc
@@ -2453,6 +2445,22 @@ functions:
     arguments:
       - type: _Float16
     guard: LIBC_TYPES_HAS_FLOAT16
+  - name: sincos
+    standards:
+      - gnu
+    return_type: void
+    arguments:
+      - type: double
+      - type: double *
+      - type: double *
+  - name: sincosf
+    standards:
+      - gnu
+    return_type: void
+    arguments:
+      - type: float
+      - type: float *
+      - type: float *
   - name: sinhf
     standards:
       - stdc