Use consistent naming for allocating SPI.

Throughout the IPsec code (API, system server, netd) we use "reserve"
SPI and "allocate" SPI interchangeably. This renames to use "allocate"
everywhere for self-consistency and consistency with the kernel
(ALLOCSPI).

In javadoc, I am leaving the word "reserve" in several places because it
is still an accurate description of how the method behaves.

Bug: 69128142
Test: TreeHugger should be enough
Change-Id: I8ea603b4612303b0393beef04032671fa53d2106
diff --git a/services/core/java/com/android/server/IpSecService.java b/services/core/java/com/android/server/IpSecService.java
index 1154fbe..72d2c4d 100644
--- a/services/core/java/com/android/server/IpSecService.java
+++ b/services/core/java/com/android/server/IpSecService.java
@@ -672,15 +672,15 @@
         throw new IllegalArgumentException("Invalid Direction: " + direction);
     }
 
-    @Override
     /** Get a new SPI and maintain the reservation in the system server */
-    public synchronized IpSecSpiResponse reserveSecurityParameterIndex(
+    @Override
+    public synchronized IpSecSpiResponse allocateSecurityParameterIndex(
             int direction, String remoteAddress, int requestedSpi, IBinder binder)
             throws RemoteException {
         checkDirection(direction);
         checkInetAddress(remoteAddress);
         /* requestedSpi can be anything in the int range, so no check is needed. */
-        checkNotNull(binder, "Null Binder passed to reserveSecurityParameterIndex");
+        checkNotNull(binder, "Null Binder passed to allocateSecurityParameterIndex");
 
         int resourceId = mNextResourceId.getAndIncrement();