soc/qualcomm/calypso: Add placeholder for early clock initialization

This commit adds the `clock_init()` function for the Qualcomm calypso
SoC. This function is now called at the beginning of
`bootblock_soc_init()` to enable SoC-specific clock setup early in the
boot process.

The `clock_init()` function definition is currently a placeholder
and will be populated with the required clock configurations in
subsequent changes.

BUG=b:496650089
TEST=Able to build google/mensa.

Change-Id: I3886670348e998b3d80d33643e2256af4eb47fd7
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/91904
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>

src/soc/qualcomm/calypso/bootblock.c

@@ -15,6 +15,8 @@ void bootblock_soc_early_init(void)
 
 void bootblock_soc_init(void)
 {
+	clock_init();
+
 	quadspi_init(SPI_BUS_CLOCK_FREQ);
 	qupv3_fw_init();
 }

src/soc/qualcomm/calypso/clock.c

@@ -16,3 +16,8 @@ void clock_configure_dfsr(int qup)
 {
 	/* placeholder */
 }
+
+void clock_init(void)
+{
+	/* placeholder */
+}

src/soc/qualcomm/calypso/include/soc/clock.h

@@ -10,6 +10,7 @@
 #define SRC_XO_HZ		(19200 * KHz)
 
 /* TODO: update as per datasheet */
+void clock_init(void);
 void clock_configure_qspi(uint32_t hz);
 void clock_enable_qup(int qup);
 void clock_configure_dfsr(int qup);